If you are on your dashboard, you may notice a mismatch between the statistics shown and your records. Note that when you are on your dashboard, it defaults to the last month of data. There is a drop down menu in the top right where you can select how far back you want to view your statistics (1 month, 3 months, 6 months, 4 years, 5 years).
Note, there is also a report that presents similar information. To access it, click on the Reports tab on the left side menu and select the Engagement Statistics report.