Looking on the internet deeply has found these results:

in the same period is the most popular phrase on the web.

during the same period 129,300,000 results on the web	in the same period 185,600,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
It doesn't look like this phrase is very popular! The search could not find any examples on the internet.	Total imports remained at similar levels in the same period. In the absence of measures, emissions of fluorinated gases would have risen by 50% in the same period. Between 2009 and the RIP, the volume of those imports increased by 24 % and the corresponding market share increased from 8 % to 9,6 % of total Union consumption in the same period. The cumulative number of HIV infections reported in the same period was 4780. According to the Chinese export database over 9 million tonnes of wire rod were exported worldwide by China during the RIP representing over 50 % of the total Union consumption in the same period. The Community producers therefore lost over 6,8 percentage points of market share in the same period. The Indian exporting producers gained 3,5 percentage points of market share in the same period. The corresponding market share decreased by 71 % in the same period.

during the same period

129,300,000 results on the web

in the same period

185,600,000 results on the web

More popular!

It doesn't look like this phrase is very popular! The search could not find any examples on the internet.

Total imports remained at similar levels in the same period.
In the absence of measures, emissions of fluorinated gases would have risen by 50% in the same period.
Between 2009 and the RIP, the volume of those imports increased by 24 % and the corresponding market share increased from 8 % to 9,6 % of total Union consumption in the same period.
The cumulative number of HIV infections reported in the same period was 4780.
According to the Chinese export database over 9 million tonnes of wire rod were exported worldwide by China during the RIP representing over 50 % of the total Union consumption in the same period.
The Community producers therefore lost over 6,8 percentage points of market share in the same period.
The Indian exporting producers gained 3,5 percentage points of market share in the same period.
The corresponding market share decreased by 71 % in the same period.