YTD Issue

Hi,

I am trying to load below data in Essbase cube (9.3.0) version.If we sum up data for Mar,Apr & May we get zero (0) value,so Y-T-D(May) should also give me zero value but its not. Can anyone let me know why YTD data is coming as zero for row 3 & 4 but not for row 1 & 2 ??

mar , apr , may , Y-T-D(may) , Y-T-D(apr)
-72360 , 25149.12 , 47210.88 , -0.00000000000727595761418343 , -47210.88
-72360 , 25149.13 , 47210.87 , 0.00000000000727595761418343 , -47210.87
-72360 , 25149.11 , 47210.89 , 0 , -47210.89
-72360 , 25149.14 , 47210.86 , 0 , -47210.86


I am loading data upto 2 decimal please only.
Please let me know if need more information

Thanks in advance