Bar count

 
I need help!
I do not know if the following is normal or not.

I have simple indicator test routine which is displaying following bars.
When "start" is executed I get three bars to be process.
Why?
Each bar is in M1 time frame so I am updating bars 3432, 3433, 3434 over 3 min. period?
Is it normal?
I would expect that only last bar should be processed and not last three.
May be I am missing something.


................... bars | cBars | L | i | Buffer
EURUSD,M1: 3435 | 3432 | 3 | 0 | 0.4
EURUSD,M1: 3435 | 3432 | 3 | 1 | -0.1
EURUSD,M1: 3435 | 3432 | 3 | 2 | -0.2