My last company had something like that and included response time percentiles (50th, 90th, 95th, 99th) and we had these values graphed and displayed on a big screen in our office. Along with a ton of other performance stats: queries per second, various measures of system load, etc.<p>Averages can lie, especially when something like an empty query can take close to zero time compared to a non-trivial transaction. If some robot or other artifact of your site is generating a some amount of null queries that will make your average response time look better than it actually is. Percentiles, particularly on the tail of 90th or above, tell a better story of how well and consistently you're responding to traffic under load.