an increase of more than vs an increase by more than

Some examples from the web:

• This translates to an increase of more than 30 percent if you compare the figure to the Netcraft SSL Survey Switzerland for September 2015.
• In the year 2000, this had already risen to seven million euro, an increase of more than 450 percent.
• In 2003, trade between Beijing and the continent amounted to 18.5 billion US dollars, an increase of more than 50% over 2002.
• This occurred against the background of an increase of more than 24 % in consumption from 2009 to the end of the IP.
• It shall also apply to any adjustment of such an operation involving an increase of more than 20% in the amount initially agreed, and proposals arising for substantive amendments in the execution of a project for which a commitment has already been made.
• The number of placements obtained to EURES, rose from 26449 in 1998 to 44460 in 1999: that is an increase of more than 68% in one year and the potential for more placement is much greater.
• The Furniture Show also posted exceptional results, with an increase of more than 10,000 square metres over 2007.
• In 2015, the group achieved a total turnover of 195 million euros, an increase of more than 25% over the previous year.

Some examples from the web:

• The revised data show an increase by more than 97 million pieces and a market share increasing from 36 % to 51 %.
• Let's summarize the main results of this quantitative analysis of the second half of the century: Overall employment increased by a factor of 2.3; wage and salary employment by 2.6, an increase by more than 76 million employees.
• In its DB 2011, the Commission had actually proposed an increase by more than 13 % of CA for enlargement, a proposal that EP welcome in its resolution on the mandate for trilogue.
• This was an increase by half compared with the average during the five preceding years.
• Italy remains the principal market, posting an increase by 12.3%.
• The Committee subsequently proposed to back an increase by 4.5 per cent, reflecting inflation since the 2004 enlargement.
• The results show that an increase in temperatures of 1.5 degrees could determine an increase by 40% of areas devastated by fires, especially in Spain.
• The small price step shall be set such that an increase by an integer number of small price steps is equal to an increase by a large price step.