Warren Buffett doesn’t owe shareholders an apology for falling short of a performance goal at his Berkshire Hathaway Inc., Vice Chairman Charles Munger said at the company’s annual meeting.

Munger said Buffett set a high bar with a target of boosting Berkshire’s net worth more than the advance of the Standard & Poor’s 500 Index over a five-year period.

Berkshire fell short in the stretch that ended Dec. 31, and Buffett said in a March report to shareholders that performance should instead be measured over the course of stock-market cycles.

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“Warren has set a ridiculously tough standard,” Munger said in Omaha, Nebraska. “If this is failure, I want more of it.”

Book value, the measure of assets minus liabilities that Buffett highlights, rose to $134,973 a share at the end of December, 91 percent more than where it stood five years earlier.

The S&P 500 returned about 128 percent during that period, including dividends, as stocks rallied from their financial-crisis lows. The Berkshire number is an after-tax figure, whereas the index results are before taxes.

Book value at Berkshire rose 2.6 percent in the first quarter to $138,426 a share. The S&P 500 posted a total return of 1.8 percent in the period.

While Buffett said that he didn’t change the yardstick by which he measures Berkshire’s performance, the shift away from a five-year target raises questions about transparency, Meyer Shields, an analyst at Keefe, Bruyette & Woods Inc., said in a note to clients dated May 1.

“In the years leading up to 2013, Mr. Buffett’s letter focused only on five-year relative performance,” Shields wrote. “The words ‘stock market cycle’ didn’t appear even once.”