The total net gain from operations at the biggest U.S. life insurers rose to $36 billion in the second quarter, up 31% from the total for the second quarter of 2008, according to the Highline Data Performance Monitor.

Highline, a unit of Summit Business Media L.L.C., Erlanger, Ky., the company that owns National Underwriter Life & Health, has based those figures on financial data from the top 100 life insurers.

Total life industry capital and surplus at the top 100 insurers increased 1.7%, and separate account assets at those insurers increased 4.3%.

Net premiums dropped 6.5%, partly because of an 8.4% decrease in group insurance premiums.