Thanks, Alisa. When I refer to annualized figures, I'm talking about the compound annual growth rate (exponential mean) for the entire backtest, which is not the same as just taking the arithmetic mean of the 12 month returns for all the years. The use case is just that relatively small changes in the CAGR can result in large changes in cumulative returns, which makes it a less robust performance metric in backtesting. This is particularly true for long backtests (I use 2003-present) as cumulative returns can often be large and hard to interpret.
I would like to request that the Quantopian team add the option to see annualized figures. The calculations are relatively simple: for example, CAGR can be calculated as (1+cumulative return)^(1/(trading days/250)).