Market cap wrong for DUK, XEL possibly others....
Market cap data is wrong for multiple companies, suggesting that the calculation has errors which is odd since it is a very simple calculation of Shares*Price=MktCap. Here are several examples:
DUK -- shares outstanding 728.05M, price $87.04, mkt cap $63.36B but website lists it at 63.49B
XEL -- shares outstanding 514.67M, price $58.39, mkt cap $30.05B but website lists it at 29.96B
These are relatively small discrepancies, but beyond differences due to rounding, so it is not clear why they are there at all. Market cap is a basic calculation.