If it didn't pay interest I suppose one could calculate the yield from the price pretty easily. (money.stackexchange.com)
One of the things to note is that because you are calculating the yield using the stock price, it will continually change with the stock price. (abcsofinvesting.net)
I don't include the cash when calculating yield (yield is calculated out of a the total of equity positions). (youngdividend.com)