The pace of bank mergers slowed in the second quarter, but deal announcements still rose about 15% in the first half from a year earlier, according to SNL Financial.

Deal volume fell 12% from the first to the second quarter, and total deal values declined 31% during the same period, an SNL report issued Wednesday said. There were 50 bank and thrift deals worth $2.15 billion in the second quarter.

There were 106 deals worth $5.28 billion during the first half of 2012, compared with 92 deals worth a combined $16.17 billion a year earlier. Capital One Financial's (COF) $9 billion acquisition of ING Group's online U.S. bank was announced in the first half of 2011.

Deal prices narrowed in the second quarter after an uptick in the first quarter.

The median price-to-tangible-book value of deals announced in the second quarter was nearly 111%, down from 116% in the first quarter.

The postcrisis downturn in bank mergers appears to have bottomed out in the second half of 2011, according to SNL's numbers. The slowest quarter by deal volume in recent years was the fourth quarter, when there were 37 transactions. The third quarter was the softest for deal values, at $270 million.