不太會Excel，但是覺得蠻有意思的，所以來試試看，用總月份來算不知道對不對。
https://drive.google.com/open?id=1gBDqPYEkc0MdJEmfBArlqNGePwqgDlrq

我用SQL寫的，不知對你有沒有用，僅供參考

CREATE  PROCEDURE [dbo].[SP_GetEmpYears]
AS
BEGIN
	DECLARE @TOYEAR AS VARCHAR(10)
	SET @TOYEAR = CAST(YEAR(GETDATE()) AS VARCHAR)+ '/4/30'  -- 實際當年的4月30日止
	DECLARE @LASTDAY AS DATETIME
	SET @LASTDAY = CONVERT(VARCHAR(10), @TOYEAR ,111)

	DECLARE @MINYEARS AS INT
	SET @MINYEARS = 5   --最少五年以上，五一勞動箱時要頒資深員工獎用的

	SELECT 
		EMPNO 工號,
		EMPCNAME 姓名,
		HIREDDATE 到職日 ,
		floor(CAST(DATEDIFF(MONTH, HIREDDATE,@LASTDAY) AS FLOAT) /12) 實際年資,
		floor(CAST(DATEDIFF(MONTH, HIREDDATE,@LASTDAY) AS FLOAT) /60)*5 五的倍數
	FROM HR.DBO.EMPLOYEE
	WHERE 
		QUITDATE IS  NULL AND DATEDIFF(YEAR, HIREDDATE,@LASTDAY)>@MINYEARS 
		and CAST(floor(CAST(DATEDIFF(MONTH, HIREDDATE,@LASTDAY) AS FLOAT) /12) AS INT) %5 = 0
	ORDER BY HIREDDATE
END

檔案已經失效了，沒辦法看。
建議把年、月換算成單一值，ex.8年6月=>8.5年，再用countifs，算出各年資區間的人數。
ex.一年以上未滿兩年，A欄為年資
=COUNTIFS(A:A,">=1",A:A,"<2")