Considering that the increases in unprocessed food and tobacco prices – which are beyond the control of monetary policy account for 5 percentage points of current annual inflation, it is clear that there is sizeable room for disinflation from this channel (Figure 31). BIS Review 159/2010  13  Factors that are beyond the control of monetary policy, such as fluctuations in unprocessed food prices and tax adjustments related to tobacco products, created significant forecast uncertainty by increasing the volatility of consumer inflation. This, in turn, has created a challenge for us to understand the underlying inflation correctly and to manage expectations. In this context, I believe that it would be useful in terms of transparency and predictability, to share with the public the assumptions we make relating to the said groups while making forecasts and our inflation expectations excluding these groups. Accordingly, we assume that annual inflation in unprocessed food products will be 17 percent for end-2010 and 9 percent for the following two years. Meanwhile, the annual rate of increase in the tobacco and alcoholic beverages group index is expected to be 24 percent at end-2010 and to hover around levels consistent with inflation targets in subsequent years. Within this scope, we expect the inflation indicator excluding unprocessed food and tobacco and alcoholic beverages to follow a volatile trend in the first half of 2011 due to the base effect and to gain stability slightly above 4 percent in the medium term (Figure 32).

[9] Transacting cryptos on blockchains can be inefficient, slow and expensive; they face the blockchain trilemma, whereby aiming for optimal levels of security, scalability and decentralisation at the same time is not achievable. [10] Crypto-assets relying on a proof-of-work validation mechanism, which is especially relevant for bitcoin as the largest crypto-asset by market capitalisation[11], are ecologically detrimental. Public authorities will therefore need to evaluate whether the outsized carbon footprint of certain crypto-assets undermines their green transition commitments. [12] Moreover, proof-of-work validation mechanisms are inadequate for large-scale use. [13] Bitcoin, for example, can only accommodate up to seven transactions per second and fees can be exorbitant. While alternative solutions to overcome the blockchain trilemma and proof-of-work consensus shortcomings have emerged for faster and more affordable transactions, including those outside the blockchain, they have drawbacks of their own. "Off-chain" transactions conducted via third-party platforms compromise the core principles of crypto-assets, including security, validity and immutability. [14] Another  important aspect is the operational risk inherent in public blockchains due to the absence of an accountable central governance body that manages operations, incidents or code errors. [15] Moreover, the handling of crypto-assets can be challenging. In a decentralised blockchain, users must protect their personal keys using self-custody wallets, which can discourage widespread adoption due to the tasks and risks involved, for example the theft or loss of a key. Given the immutability of blockchains, they do not permit transaction reversal. [16]  Instability Another key limitation of unbacked cryptos is their instability.