Looking on the internet deeply has found these results:

increase in is the most popular phrase on the web.

increase on 17,480,000 results on the web	increase in 1266,000,000 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.	Unquestionably through an increase in employment and productivity. The increase in spending on research and innovation is justified. The increase in appropriations essentially benefits the new Member States. Investment returns also contributed positively to the increase in market value. Fishing opportunities may increase in certain conditions mentioned in the agreement. The increase in safety and reliability will be palpable. There has been no sudden calamitous increase in imports. The tractor division should show an increase in earnings.

increase on

17,480,000 results on the web

increase in

1266,000,000 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.

Unquestionably through an increase in employment and productivity.
The increase in spending on research and innovation is justified.
The increase in appropriations essentially benefits the new Member States.
Investment returns also contributed positively to the increase in market value.
Fishing opportunities may increase in certain conditions mentioned in the agreement.
The increase in safety and reliability will be palpable.
There has been no sudden calamitous increase in imports.
The tractor division should show an increase in earnings.