Problem: how many weeks between 18-07-2012 and 05-05-2014
how many fortnightly payment dates between 18-07-2012 and 05-05-2014
There are 656 days between the two dates. Divided by 7 gives 93.714 weeks.
However, you ask about fortnightly payments, which means every TWO weeks.
93.714 weeks / 2 = 46.857
The answer must be 46 payments