Inconsistent Timezone on MT4. Data analysis problem. Help!

 
Hi guys!

Context:
I am currently using past data to do some profound analysis (Just started out using SQL) and of course using excel.

Problem:
Specifically, I am looking at NZD retail sales. It is clear that some years it is at 00:45 and other years at 01:45 ... and I am looking at summer months so it is not DST.


           


Does anyone else around do this kind of stuff? Have any ideas why it might be different year by year? 

In any case have a nice weekend!

Thanks :)

Vic