Time shift in exported data

[pinokio88]

Hello,

I read a lot of threads about exporting data and different time and timeshift, but no-one answered to my question.

I am in CET timezone (GMT+1 - Czech Republic) and I downloaded historical data from Zen-fire datafeed (E-mini S&P 500 (ES) market).

Here is "main trading hours" (compare by volume):

2009-04-02 14:30:00 - 21:15
2009-04-04 = First Sunday in April
2009-04-06 13:30:00 - 20:15
...
2009-10-23 13:30:00 - 20:15
2009-10-25 = Last Sunday in October
2009-10-26 14:30:00 - 21:15
...
2010-04-01 14:30:00 - 21:15
2010-04-04 = First Sunday in April
2010-04-05 13:30:00 - 20:15
...
2010-10-29 13:30:00 - 20:15
2010-10-31 = Last Sunday in October
2010-11-01 14:30:00 - 21:15
...
2011-04-01 14:30:00 - 21:15
2011-04-03 = First Sunday in April
2011-04-04 13:30:00 - 20:15
etc...

I suppose that time shift is because Daylight Saving Time, but WHY is changes in first Sunday in April and last Sunday in October?

In USA, DST starts on the second Sunday of March, and it ends on the first Sunday of November.
IN Central Europe DST starting on the last Sunday in March and ending on the last Sunday in October.

Interesting information is, that from 1986 to 2006 DST was from the first Sunday in April to the last Sunday in October (this is the same as i my case):

http://www.infoplease.com/spot/daylight1.html#ixzz1eguZTT8M

My question is why is this time shift? Can I remove it somehow? (for example change timezone in computer and download data again, etc...). I do not mind the data will be in UTC or different timezone.

Thank you very much and sorry for my English.

pinokio88

[NinjaTrader_Bertrand]

Welcome to our forums pinokio88 : when you export the data with NT it's exported in UTC per default (that's why the default import zone set is UTC as well here).

As you download the data NT would store it locally and stamp / sort it according to your local PC set timezone - we have seen a few issues with incorrect DST offsets which to a large degree be caused by missing updates for your OS / .NET - have you checked via Windows Updates if there are any outstanding patches to be applied to your system?

Which OS would you be using here?

Once patches are applied please download a fresh set of data and recheck it.

[pinokio88]

This is it ;-)

I updated my .NET and now it is OK (by the way my OS is WIN XP).

Great, thank you very much

[NinjaTrader_Bertrand]

Thanks for reporting back, glad to hear it.