It’s becoming harder to find a bank that hasn’t already laid off at least 10% of its staff. But with revenues still catastrophically low, headcount reductions to date could prove a pinprick compared to what’s coming next. Based on average pay per head for the year so far, we’ve calculated how many more people each bank would need to cut in order to maintain its compensation ratio (compensation costs as a percentage of revenues) in line with 2007. The results range from the farcical (Merrill Lynch) to the disturbing (Credit Suisse), and the reassuring (Goldman and Morgan Stanley).