Last year Report has got the wrong start and end dates

Problem/Motivation

these two lines
$dates['start'] = date("Y-M-d", $this_year_start);
$dates['end'] = date("Y-M-d", $this_year_end);

need to be:
$dates['start'] = date("Y-M-d", $last_year_start);
$dates['end'] = date("Y-M-d", $last_year_end);

Steps to reproduce

Proposed resolution

Remaining tasks

User interface changes

API changes

Data model changes