It is wrong - or at least redundant - because, apparently, there is no order required.
We use "respectively" only when indicating that a previously established order is being reused. For example:
First, second and third places in the race were won by John, Paul and David respectively.
This means that John came first, Paul came second, and David came third. The order in which the names were listed was the same as the order in which the race positions were listed.
Your example is just two numbers, and evidently, it does not matter which order they appear in.
Another example would be "my two children are aged 5 and 8". There is no need to add 'respectively'. Even if it were relevant when they were born, the order is obvious. On the other hand, you might say "my children, Oscar and Olivia, are 5 and 8 respectively", because this establishes that Oscar is the 5-year old and Olivia is the 8-year old.