Hello Ossaio,
if you have a starting point in the script, you will still need to adjust it for each time frame. Starting at 01.01.2017, for example, will be a different count of bars for all time frames. So you will still need to calculate it.
Basically, when we generate strategies we focus on the count of bars because this is in correlation with the count of trades.
Or you want to use the last 5 years for all time frames? If so, just what Sisi says will work best for you. Set starting point in FSB Pro or EA Studio.