Countif not Counting correctly

[Liphor]

What"s wrong with my countif formula as I find 2 different answers for 2 different sheets. Attached is my file with the formula cells colored orange and the range cells  colored yellow.

[#2]

@Liphor On the first sheet the yellow range indeed only contains 28 cells not equal to 0, compared to the 2nd sheet that 29 cells not equal to 0. The difference lies in the fact that the first sheet does not have the year 1991 in it.

By the way, you can change the formula to

=COUNTIF($N$14:$N$63,"<>0")

[#3]

@Liphor 

There is no error, please look you data carefully

If manually check in sheet Ann_RF the cells having value not equal to two value & not equal to zero is 28

The year starts from 1992 to 2019

Whereas in sheet Ann_Q the cells having value not equal to two value & not equal to zero is 29

The year starts from 1991 to 2019

[#4]

Oh sorry It is my oversight on the data. Technically I should be using the same number records for both sheets.

[#5]

Oh sorry It is my oversight on the data. Technically I should be using the same number records for both sheets. I accidentally deleted a record.Thank You.