Sum yearly totals automatically
Insert a column between column A and B (you can hide this column after).
Fill the cells of this column with the following formulae:

YEAR(A2)


The column should be A for all cells, and the row number should be incrementing, such that the cell being referred to is always the one immediately to the left.
In column D, fill the following formulae:

SUMIF(Year,"=2015",Amount)


Replace ‘Year’ with the column heading for the column you created in step 1.
Replace ‘2015’ with the year that you are looking to be summed for that cell.
Hide the column you created in step 1 (right-click on the column and choose Hide Column).