The Crypto Winter of 2022
Crypto-currency crashes and network failings
2022 has shaken the crypto market and seen two trillion dollars in losses caused by price drops in several cryptocurrencies, network and exchange failings.
Some of the biggest shocks to the market thus far have been the collapse of Terra LUNA/UST, Celsius Network’s filing for bankruptcy, Voyager Digital’s filing for bankruptcy, and the collapse of Three Arrows Capital. These shocks do not come in isolation and have rippled across the market, leading to overall price declines of Bitcoin and Ethereum. The resultant issues which appear to be most problematic are where users’ cryptocurrencies are locked in accounts handled by exchanges, or where the management of their funds is left in the hands of others.
Investors in large, failing, exchanges who have lost funds in this ‘crypto winter’ are left wondering what remedies are available to them and if they can claim back from any irresponsible actors in this system.
Remedies under the current regulatory regime are ineffective. Most investors sign away their rights to their crypto in voluminous terms and conditions of crypto-exchanges and many will (at best) rank as unsecured creditors should these exchange services be liquidated. Crypto exchange and crypto investment service providers are essentially operating as banks, but without the safeguards and regulation which banks are required to follow. The underlying principles for recent crashes are not extraordinary or novel, they can be found in the same irresponsible practices which lead to the 2008 crash in the traditional financial market. The effect of these irresponsible practices and the ripple it sends across the market are also not novel, especially in a market which is arguably based more on consumer expectations than any other. The answer to many regulators’ questions of how to protect consumers in the crypto-market is to apply comparative safeguards found in traditional finance. Namely: regulate the minimum reserves which may be held by any exchange, mandate that these service providers must be licensed, regulate risk exposure, apply standards of transparency, and include crypto-currency within the meaning of a financial product.
This brings us to the first, perhaps most significant, recent crash of Terra USD and Luna. Once lauded for providing cutting-edge blockchain investments to users worldwide, Terra is now blamed as the catalyst for the 2022 Crypto Winter. What went wrong, and why, are key questions the market has been coming to grips with — along with the regulators.
2. Terra Luna/Terra USD (a cryptocurrency crash)
2.1. The crash
Terra USD (‘UST’) is a supposed stablecoin out of Terraform Labs. The coin was pegged to the dollar by means of an algorithmic peg, using another Terraform cryptocurrency LUNA to maintain its peg. The system worked by an arbitrage network, where LUNA and UST were exchanged for one another — one being sold for the other when there was a profit to be made, creating demand for the cheaper currency up and bringing its price back up. For a time this worked and UST was able to keep close to a 1:1 ratio with the dollar. This mechanism also burns the cryptocurrency being exchanged, which had an important role in the crash.
Part of Terra’s ecosystem and stabilizing mechanism was the Anchor Protocol (“the Protocol”), which operated similar to a savings account into which volumes of UST were deposited to earn a high long-term yield. At its peak, Anchor held almost 75% of all UST in circulation — making the value of UST highly dependant on the functioning of this pool.
The Protocol received UST from lenders, lending it out to borrowers to achieve a roughly 20% yield for lenders — functioning much like a bank would. This return became variable from March this year, fluctuating up and proportionately with the reserves (the amount of capital reserved by Terra to satisfy the return) held by the Protocol. With lenders increasing, drawn in by the promise of high rewards, reserves began dwindling to pay them their yields. One temporary fix was to inject more UST into the Protocol and bolster reserves. Clearly, this did not last as the Protocol was not attractive enough to keep users invested with constant capital deposits.
In May 2022, $2 billion worth of UST was withdrawn from the Anchor Protocol and liquidated. This put pressure on LUNA as arbitrageurs sought to take advantage of the price difference, widening a gap between LUNA and UST which was never supposed to grow so large in the first place. The Luna Foundation attempted to bridge this gap by injecting more UST into the system (remember UST is burned as LUNA is minted), seeking to regain control and balance the price of both cryptos.
With the flood of LUNA entering the market, it too could not sustain its value and plummeted. Efforts by the Luna Foundation to use Bitcoin in reserves and use it to stabilise UST/LUNA also failed, resulting in a simultaneous injection of Bitcoin into the market — an oversupply which caused the price of Bitcoin to drop
2.2. What went wrong?
A combination of issues led to the Terra crash: poor reserves, a flawed algorithm, and no withdrawal limit on the Anchor Protocol.
Had there been restrictions in place to account for large withdrawals then perhaps UST would not have lost its peg
Jump Crypto reviewed UST/LUNA activity in May 2022, finding that only a few large transactions were responsible for the instability and crash of the currencies. These transactions have been traced back to a small number of wallets, the identities of all these wallet holders is still unknown. It is cause for concern that such a select few were able to destabilize an entire cryptocurrency ecosystem without consequence or accountability. This will be discussed further below.
For a more comprehensive analysis of what went wrong with Terra, see the report by Nansen https://www.nansen.ai/research/on-chain-forensics-demystifying-terrausd-de-peg
2.3. The Anchor Protocol Withdrawal
The $2 billion withdrawal of UST from the Anchor Protocol has been traced back to seven wallets, including the Celsius Network.
The chart below illustrates UST’s increasing deviation from the peg as UST was withdrawn from Anchor.
In the course of Nansen’s analysis of the de-pegging of UST, the seven wallets significantly affecting the de-peg are listed below. One of these wallets has been identified as belonging to Celsius, whose withdrawal from the Protocol caused more harm than good. This is discussed further in the following section.
The actions of a few major UST holders were enough to destabilise the Terra ecosystem and put small wallet holders out of pocket, with no recourse available to them.
It is alarming that, as we will see, the crash of Terra was directly responsible for the crashes of many crypto-hedge funds and networks. These funds and networks were over-exposed to one “stablecoin” (an algorithmic one at that), a risky investment decision which has left millions of users’ investments devalued.
That being said, Terra cannot be blamed in isolation for the effects of its crash and the lack of prudential practice by major lenders and investors in the crypto-market must take its share of responsibility.
3. Celsius Network (a crypto exchange crash)
The Celsius Network, a prominent crypto-exchange platform, filed for bankruptcy in the United States. This came after a month of uncertainty following Celsius freezing investor accounts on June 12th, a move which came almost without warning and was precipitated by poor liquidity in the exchange.
The reasons why Celsius could not satisfy investor withdrawals are still coming to light but they appear to be a combination of over-leveraged loans (and poor reserves), poor decision-making by prominent actors, and potentially a degree of malfeasance by major crypto-asset holders and Celsius executives.
3.1. ETH & stETH
To understand the recent crash of the Celsius network and its associated token CEL, a discussion of Celsius’ staking practices is explained briefly below.
Celsius was heavily invested in stETH, a token representing ETH (ether, the Ethereum network token) staked in the Ethereum 2.0 beacon chain — a secondary “upgraded” Ethereum blockchain using a different validation method. The purpose of stETH is to earn rewards on the ‘upgrade’ of the ETH platform. The Merge transitioned the current Ethereum network from a proof of work consensus mechanism (validation method) to proof of stake. stETH is essentially ETH which is locked away in a decentralised smart contract, earning rewards for long term investors maturing at the Merge. With the object of earning rewards, users staked their stETH into liquidity pools on various networks, which pegged the price of stETH at the price of ETH. This allowed them to earn rewards on a future value of ETH on the new network.
Celsius users relinquished their keys to their ETH tokens to Celsius, which then staked these tokens in smart-contracts — into stETH. stETH was traded for ETH in the Curve liquidity pool when Celsius wanted to withdraw ETH. The overtrading and withdrawals of stETH for ETH led to a destabilizing of the 1:1 price peg — an increase in demand lead to an increase in the price of ETH. This meant that Celsius could not realise the same amount of ETH to satisfy customer withdrawals, with the Curve pool drying up. The first de-pegging of stETH coincided with Terra’s collapse as users sought to trade back to the main network, fearing instability. The second event, which Nansen shows exacerbated the de-pegging, came as other large players tried to unwind their positions in stETH.
This caused a run on Celsius with users panicking to withdraw their investments, consequently causing Celsius to freeze its network. The ensuing liquidity crisis resulted in Celsius filing for liquidation on 17 July 2022.
3.2. Anchor Protocol
Celsius had a substantial investment of user funds within Terra’s Anchor Protocol. While it withdrew most of these funds before Terra’s crash, this proved to be a double-edged sword. By withdrawing these funds and contributing to the de-pegging of UST, consumers became panicked at instability within the crypto-market — leading to widespread withdrawals of cryptocurrency and price declines.
This consequently affected Celsius’ other holdings, particularly Bitcoin which was directly affected by Terra’s attempts to stabilize UST (leading to a decline in the price of Bitcoin).
3.3. Bad loans
In its Chapter 11 bankruptcy filing, Celsius attributes 30% of its loans to users as representing bad debt — approximately $310 million. These are loans which borrowers (from Celsius) cannot pay off and are essentially written off Celsius’ books.
Celsius has further disclosed a debt due to it by Three Arrows Capital of nearly $40 million — which it will be unlikely to realise given the bankruptcy of that hedge fund.
Overall, the exchange reported a deficit on its balance sheet of nearly $1.2 billion — which CEO Mashinsky attributed to “bad investments”.
3.4. Alleged malfeasance and lack of regulation
Since the freezing of investor accounts in June 2022, several lawsuits have been filed against the Celsius Network, some of which allege outright fraud on behalf of the company.
Some of the actions taken by Celsius prior to the freezing of investor accounts have yet to be explained by the company, such as a $320 million payment to the FTX exchange and the overleveraged positions taken by the company. The payment made to FTX was made shortly before customer accounts were frozen, purportedly in repayment of a loan. This would, in ordinary liquidation proceedings, be considered preferential treatment of a creditor in circumstances where company insolvency was imminent. Usually, when this occurs a court may order the payment reversed so that creditors can be treated fairly according to their ranking — even where the creditor is faultless in receiving the preferential payment.
The above statistics are the last weekly statistics (that we have found) provided by Celsius before it froze customer accounts on June 12th . The week of May 6 — May 12 shows massive outflows and negative holdings.
Celsius essentially behaved as a bank, but without the institutional framework supporting bank practices. The practice of taking customer’s assets (cryptocurrency) looks very much like taking deposits in traditional finance, which is a heavily regulated practice. Lending those deposits on further by staking them in pools also looks very much like what banks do with customer deposits, albeit without the insurance provided in traditional finance.
CEO Alex Mashinsky’s tweets leading up to Celsius’ crash were all deliberately misleading. This may, at the very least, amount to a breach of a fiduciary duty he holds towards Celsius. There are also accounts of Mashinsky telling the public outright that Celsius had minimal exposure to UST — which it did not as it was one of the largest wallets influencing the de-pegging of UST.
Indeed, up until June 12th, Celsius was actively trying to entice new customers with promotional offerings designed to attract liquidity and offering rewards to customers who allowed their crypto to be locked away for six months.
The tweet by Mashinsky on June 12th is a response to a user query on withdrawals, which has reportedly not been functioning properly for several days before accounts were frozen.
Given that cryptocurrency is not regulated as a financial product or as fiat currency, Celsius cannot be said to have breached regulation. However, they can be found to have behaved negligently by not implementing prudent practices and/or deliberately misleading consumers.
Regardless, now that Celsius has filed for bankruptcy, consumers are left wondering what remedies are available to them — the answer is not many.
3.5. Consumer rights in Bankruptcy
Celsius filed for Chapter 11 bankruptcy in July 2022. In the United States, this is a procedure which allows restructuring of corporate debt in order to keep the company in business.
In general, Chapter 11 bankruptcies prioritise repayments to secured creditors, then unsecured creditors, and then equity holders. The bulk of account holders with Celsius are unsecured creditors who will receive repayments only after secured creditors (who typically have the highest outstanding debt) are paid, and then only proportionally based on the available assets left in the pot.
This is because on depositing fiat or cryptocurrency into Celsius, that currency becomes part of a pool with other users’ deposits (“commixtio”). The user thus does not have a right to return of that particular fiat or cryptocurrency but to a return of the value of their contribution and subject to the agreement with Celsius, which is detailed in the terms and conditions. The same protections and ownership rights which apply in ordinary banking law relating to deposits do not apply to crypto exchanges, and the agreement with a crypto exchange may disclaim them from liability for total loss of the deposit.
The risk of complete loss of a user’s holdings with Celsius is disclosed and disclaimed in Celsius’ terms:
“By lending Eligible Digital Assets to Celsius or otherwise using the Services, you will not be entitled to any profits or income Celsius may generate from any subsequent use of any Digital Assets (or otherwise), nor will you be exposed to any losses which Celsius may suffer as a result thereof. You are, however, exposed to the possibility of Celsius becoming unable to repay its obligations in part or in full, in which case your Digital Assets may be at risk.”
It is also worth remembering that depositing a fiat contribution is no different here than depositing a digital asset. Ordinarily, when lending an asset out to be used and generate a return, the owner will retain ownership rights. The owner will be entitled to demand delivery of their asset (to vindicate their asset). This is not the case here as depositors give up their ownership rights to their crypto-assets, having only an unsecured right to the value of their contribution.
“You grant Celsius, subject to applicable law and for the duration of the period during which you elect to utilize the Eligible Digital Assets in the Earn Service (if available to you) and thus loan such Eligible Digital Assets to us through your Celsius Account, or as collateral under the Borrow Service (if available to you), all right and title to such Eligible Digital Assets, including ownership rights, and the right, without further notice to you, to hold such Digital Assets in Celsius’ own Virtual Wallet or elsewhere, and to pledge, re-pledge, hypothecate, rehypothecate, sell, lend, or otherwise transfer or use any amount of such Digital Assets, separately or together with other property, with all attendant rights of ownership, and for any period of ownership.”
Crypto-exchanges will be the first place regulators control when regulating the crypto industry. While praising the decentralised aspect of decentralised finance, these exchanges are in fact centralised — acting as centrally controlled access points to the crypto-market. Investors into crypto-exchanges do not have rights to their ‘deposits’ as they would in traditional finance, where deposits have special protections under law. Traditional finance also prescribes a degree of transparency to depositors which is not offered by crypto exchanges. This combination of removing control of cryptocurrency from investors and a lack of transparency distorts the purpose of the blockchain and decentralised finance altogether, leaving investors to wonder why they chose decentralised over traditional finance in the first place. Further below is a discussion of some of the regulations which may be put in place which would, if applied intelligently, not only protect the industry but grow it.
4. Three Arrows Capital (a crypto hedge fund)
The collapse of Three Arrows Capital (3AC) came as a surprise to many in the industry in mid-2022. 3AC is a crypto-asset hedge fund, founded in 2012, which invested in crypto-assets from 2017. 3AC’s strategy primarily dealt with crypto-derivatives, but the portfolio also included investing in crypto-companies developing crypto-products and technology. 3AC’s AUM swelled to $10 billion at its height.
3AC’s fall is linked to its exposure to Terra. 3AC had bought 10.9 million LUNA at $500 million, which coins were then locked away and staked. With the collapse of Terra, 3AC’s holding diminished and its stake of LUNA is now worth a mere $670.
3AC also held a large portion of Grayscale’s Bitcoin Trust (“GBTC”), which has been trading at a discount since the rise of crypto-ETFs. 3AC concentrated on GBTC arbitrage after Terra’s crash, hoping that if the GBTC were approved for conversion to an ETF, that the discount would reverse. This did not happen and the price of Bitcoin diminished as Terra sold its Bitcoin reserves, further depleting 3AC’s other holdings. 3AC had also leveraged its GBTC shares to purchase stablecoins, which comes back to its purchase of Terra, all to attempt to repay some of its Bitcoin loans. 3AC is no longer a GBTC holder, having sold its interest at an undisclosed time — presumably at a loss.
Like Celsius, 3AC was also exposed to stETH — also losing value as stETH depegged. To add to all of this, 3AC was reportedly a significant borrower of crypto-assets — especially Bitcoin — which will presumably show as a bad debt on those lenders’ books now. Voyager Digital was one of those lenders, lending 3AC an unsecured loan of $660 million. Voyager Digital has now filed for bankruptcy as well.
3AC is a prime example of the interconnectedness of the crypto-market where relatively small shocks have a wide impact on an over-leveraged, under reserved ecosystem. Terra was after all, one exchange and one system among many and it could not be insulated from those many. Although, critics point out that 3AC was exposed to as many lenders as possible, many of whom took deposits from retail consumers in the ordinary course of business, maxing out their debts. This is how 3AC’s investment decisions affected not only institutional customers but retail customers as well, filtering down to ordinary users of networks who had made bad loans to 3AC.
Aside from questionable investment decisions, 3AC was also censured by Singaporean authorities for making misleading and false disclosures to lenders in order to receive larger loans — allegedly committing fraud.
As Decrypt reports:
‘In an affidavit filed June 26, Blockchain.com’s Chief Strategy Officer Charles McGarraugh also revealed that 3AC co-founder Kyle Davies told him on June 13 that Davies tried to borrow another 5,000 Bitcoin from Genesis, which at that time had a value of about $125 million, “to pay a margin call to another lender.” Such behavior is common within a Ponzi scheme, when earlier investors are paid with funds from newer investors.’
This highlights the issue of lack of prudential oversight of crypto-asset loans, with an industry failing to check rampant risk exposure taken by big players in an effort to make quick returns.
5. Underlying market influences
These crashes are exacerbated by macroeconomic factors currently putting the global economy under stress. Hiking interest rates, a war and shortages of fuel and grain all contribute to consumer expectations — which drive market behaviour even crossing over into crypto-assets.
With the global financial outlook growing dimmer, consumers are looking to reduce risk and seek safer investments, both safer crypto-investments and traditional investments. This includes investing in less risky crypto-products, such as ETH over stETH.
Without any security to consumer deposits in crypto there is greater fuel for panic and ‘runs’ on exchanges and staking pools — which is exactly what happened in Celsius and Anchor. Market manipulation is growing clearer to regulators, demonstrating a need to enforce checks and balances among major institutional role-players in the crypto-market. The regulatory uncertainty further adds to poor consumer expectations and drives the market towards investments which are deemed safer.
The crypto-market is part of the global economy and as such will also experience ups and downs depending on the pinch ordinary consumers are feeling. However, this being said, the cycle of ups and downs in the industry can be flattened with regulatory intervention so that shocks to the system don’t have as catastrophic an effect as has recently been felt.
6. Need for regulatory reform
Economists have competing theories of why and when to regulate. These theories can easily be applied not only to banks but also to crypto-exchanges and institutions which offer similar services to banks — taking deposits, generating interest and lending out. These theories will usually touch on concerns relating to monopolies, asymmetry of information and externalities.
Negative externalities are where is a cost that is suffered by a third party as a consequence of an economic transaction. In banking, examples include (i) contagious runs on solvent banks; (ii) economic distress or collapse due to bank failure; and (iii) increases in the cost of government provided deposit insurance.
Monopolists in banking can lead to unfairness to consumers where large players can manipulate the market without competitors to challenge them.
Information asymmetry deals with the exploitation of consumers due to lack of transparency, leading consumers to make adverse decisions. Consumers often lack the sophistication to match banks in their understanding of investments and risk, and they require protection.
The way the recent shocks have affected the crypto-market clearly shows elements of all three issues above. The market has clearly suffered economic distress after the collapse of multiple crypto-exchanges and investment funds. The concentration of the market between a few large players shows possible manipulation (consider the few wallets which destabilized the Anchor protocol) both on chain and using social media. The interconnectedness of the market also fails to insulate players from one another where one goes insolvent. The lack of transparency in these exchanges and investment funds — where consumers don’t actually know what is being done with their funds, or understand what they are told — is clearly a problem of asymmetrical information.
All of these issues provide good reason for some regulation of the industry in line with regulations available in traditional finance, so that consumers will both be protected and will have access to remedies when experiencing loss.
6.1. Remedies available in traditional finance
6.1.1. Central Bank Insurance
After the Great Depression many central banks worldwide adopted mandatory insurance practices which compelled banks to insure deposits up to a minimum amount, ensuring that consumers are protected if a bank goes insolvent.
This provides security to depositors and boosts confidence in banks during times of financial hardship, ensuring there are fewer runs on banks. Even in countries without explicit deposit insurance schemes, central banks may exercise their discretion to compensate consumers who lose their deposits in failed banks — on a case-by-case basis.
The safety net of deposit insurance is a remedy available to consumers in traditional banking which is not available to depositors into crypto-exchanges (like Celsius).
6.1.2. Prudential Supervision
In traditional finance banks are subjected to the authority of the central bank and prudential supervision — essentially ensuring that banks operate in line with best practice. It would be irresponsible for central banks to insure private banks engaging in risky practices, and using taxpayers’ money to pay out when these practices come to a head and private banks are forced to close.
A strong regulatory regime both providing rules for taking consumers’ deposits and supervising how those deposits are used ensures that fewer banks fail and improves confidence in the banking system.
Many central banks around the world supervise private banks based on these factors: capital, asset quality, soundness of management, earnings, liquidity and sensitivity to risk (if risk is being managed soundly). This can similarly be applied to crypto investments and exchanges.
6.2. Remedies available to consumers
In traditional finance, most consumers will have a remedy in being able to approach the relevant prudential authority, or at least using overarching legislation as a framework, when prejudiced by imprudent (or unlawful) banking practices.
At present across most jurisdictions, consumers will largely have rights as unsecured creditors where exchanges or investment vehicles file for bankruptcy. As discussed above, this usually puts them at the end of a long line of creditors and very little is paid out to them.
Consumers will also need to look to their contracts with exchanges and investment companies in seeking remedies to their losses. Unfortunately, many of these (especially fine print ts&cs) are broad and disclaim wide losses that consumers may suffer. Consumers should, at present, read all the terms applicable to their investment and unless they are comfortable suffering the most adverse circumstances covered in those terms, refrain from investing.
Naturally, if there are elements of fraud in the dealings of any companies which causes consumers to lose on their investments, then these consumers may have remedies in civil law and can sue for damages. This is a long and costly process however, and not worth the time and cost for most consumers.
There is, as with most industries, also a security risk. Because of the often jurisdictionless and anonymous nature of crypto-transactions, hacks are difficult to trace. This is something regulators will need to bear in mind when imposing minimum regulations, which will likely impose accountability on exchanges for losses to consumer wallets.
7. Pending Regulation
Most jurisdictions worldwide have plans to regulate cryptocurrency. Some want to declare it a commodity, others legal tender, others a financial product.
In the EU, there are current requirements under anti-money laundering directives for crypto-asset service providers to obtain a license to provide these services. This is not the same as a license required to provide financial services and does not come with the same reporting standards. The Markets in Crypto-Assets (MiCA) bill is moving through the European Parliament and is expected to pass in 2024 — it brings crypto-asset service providers more in line with the financial industry.
MiCA has the following objectives:
- To provide legal certainty for crypto-assets not covered by existing EU financial services legislation, for which there is currently a clear need;
- To establish uniform rules for crypto-asset service providers and issuers at EU level;
- To replace existing national frameworks applicable to crypto-assets not covered by existing EU financial services legislation; and
- To establish specific rules for so-called ‘stablecoins’, including when these are e-money.
Crypto-assets already defined as financial instruments or electronic money (e-money) under the Markets in Financial Instruments Directive (MiFID) and the Electronic Money Directive (EMD) are out of scope for MiCA. MiCA aims to harmonise regulation and ‘catch’ those crypto-asset activities which fall out of existing legislation.
The bill inter alia imposes licensing requirements on crypto-asset service providers and imposes reserve requirements on stablecoins. MiCA does not deal with all aspects of the wide cryptoworld, but it does deal with some of the bigger issues in the market — specifically addressing the services offered by crypto-exchanges and imposing duties of consumer protection.
Worldwide, the crypto-industry would benefit from regulation of crypto-assets that both imposes prudential standards on the industry (mandating thresholds and reporting for safe practices) and provides consumers with a clear avenue to enforce their rights, with a clear regulatory body to seek protection from. These regulations would discourage over-exposure to risky assets and encourage market confidence in the industry.
The recent decline of the crypto-market has shown the flaws in the system and the need for regulation to reign in irresponsible actors and protect consumers. Terra’s crash was not isolated and was the tipping point to expose the over-leveraged portfolios of several crypto-hedge funds and exchanges. Celsius was one of these exchanges and was not only overexposed to Terra, but one of the main actors spurring the run on the Anchor Protocol. Exposure to stETH, another instrument which would de-peg, deepened Celsius losses. 3AC is perhaps one of the most illustrative cases of the ripples sent across the industry. As a major borrower and subsequent bad debt on the books of exchanges, 3AC’s over leveraged position sent it into voluntary liquidation. Amongst all this turmoil is the behaviour of the executives of these funds and exchanges, who essentially gambled with others’ money and see few repercussions themselves.
Actors within the crypto-market may be private ventures, such as hedge funds, and yet still affect the general market where the are exposed to a large proportion of market resources. Imposing regulation to all actors with the potential to destabilise the market as we have seen recently will provide much needed protection to consumers and assist in long-term market stability.