Since 1 New Zealand Dollar is equal to 0.620799900672016 United States Dollars, we could say that n New Zealand Dollars are equal to 0.620799900672016 times n United States Dollars. In other words, we could use the following formula:
United States Dollars = New Zealand Dollars x 0.620799900672016
For example, let's say that we want to convert 2.0 New Zealand Dollars to United States Dollars. Then, we just replace New Zealand Dollars in the abovementioned formula with 2.0:
United States Dollars = 2.0 x 0.620799900672016
That is, 2.0 New Zealand Dollars are equal to 1.241599801344032 United States Dollars.