Retrieve multi-year data based on a table with Year and Week Number columns

I have business data (simplified) that has a table with columns: Year, WeekNo and Amount.
e.g. (all amounts are examples only)
2017, 4, 10.00
2017, 5, 20.00
2017, 6, 15.00
2017 ....
2017, 51, 23.00
2017, 52, 24.00
2018, 1,