Pensions for top executives rose an average of 19% in 2008, with more than 200 executives seeing pensions increase more than 50%, according to a Wall Street Journal analysis.

The executive-pension growth stemmed partly from generous pension formulas, which are based on executive pay, according to the filings. Also adding to the pension jumps are arcane techniques that have received little scrutiny, including increases triggered when an executive reaches a certain age or when companies change interest rates used to calculate...