excel udf被调用太多次了

I have a excel function defined in a module which is called a total of two times as a worksheet functon. However when I do a shift+f9 and place a breakpoint on the function, i noticed that its getting called more than twice, around 5 times. This function however is not being called anywhere else, both programmatically or in any worksheet except for the two cells i mentioned above. I have a excel function defined in a module whi