For the conservation buffer, we looked at actual pre-SCAP losses incurred by large banking firms during the recent stress period and SCAP estimates of additional losses associated with the recent stress period. Both these determinations required considerable judgment, and thus we developed ranges, rather than point estimates, for the levels we thought reasonable.
In particular, government capital injections and debt guarantees in the fall of 2008 complicated the estimation of losses that might have been incurred in the absence of too-big-to-fail support. The ratios agreed to in Basel were at the lower end of, though still within, the ranges we had calculated.