V to n
I.3 The 'amount' groupThese verbs are used when indicating a total or the result of a calculation. They are link verbs (see Chapter 5).
The noun group following the preposition to is always an amount. This pattern is V to amount.
amount come add up average out
He said defence spending amounted to 17,600 million rupees that year.
In 1894 Hamilton scored 196 runs, which averaged out to slightly more than 1 per game.