WHEN do 1.5 and 16 add up to 72?
That's the riddle confronting investors in Pershing Square Holdings Ltd, the closed-end fund run by the prominent activist investor Bill Ackman.
In a letter to investors this month, Mr Ackman disclosed that through the end of November, the fund had declined 13.5 per cent this year after accounting for fees. (Pershing Square Holdings shouldn't be confused with Pershing Square LP, Mr Ackman's hedge fund, although the two vehicles have the same investment strategy.) That's obviously a big disappointment, considering the Standard & Poor's 500-stock index was up 7.6 per cent over the same period. But that's not what some big investors were complaining about to me this...