Trainee retention rates across the U.K.’s top 30 law firms have been hit by the ongoing economic downturn, with most firms with March 2010 intakes retaining under 80 percent of their newly qualified lawyers.

Legal Week research shows the average retention rate for March 2010 stood at 75 percent, comparing acceptances with the number of qualifiers, a drop of nearly 10 percent on the 83 percent retention rate reported in March 2009.