Before revision:  As as consequence, record statistics of uncorrelated, biased, random walks provide an attractive new estimator of Sharpe ratios  .
After revision:  As as consequence, record statistics of uncorrelated, biased, random walks provide an attractive new estimator of Sharpe ratios based the total duration of drawdowns. Its efficiency is several times larger than moment-based estimators for symmetric heavy-tailed price returns. Such type of data also leads mechanically to a larger number of expected price records, hence, to a smaller duration of drawdowns. Thus, for a given number of records, the absolute value of the estimated Sharpe ratios is smaller when price returns are heavy tailed. This means that moment-based estimators are prone to overestimate true Sharpe ratios in difficult market conditions, which implies that using them for investment decisions may amplify large price returns .