Cumulative in line chart

[fj181]

Hello,

I faced a problem trying to put cumulative in a line chart, my variable are starting from 0 when a new month starts eg above.

value   objective reality

1. 30 ---30 ------   30

2. 25 -- 55 -------  25

3. 39 -- 94 -------- 64

My cumulative variable is:

My objective is that my variable can accumulate since my first date.

What i'm doing wrong? 

Thanks in advance,

________

CumulativePeriod(_Sum_, 'Entidades em Aberto'n,
_IgnoreAllTimeFrameFilters_, 'Data Estado Alerta'n, _Inferred_,
_Inferred_, 0, 12, _Full_, {Date})