After a company audit of its Facebook Page Insights Reporting tool, the social network discovered “bugs that impacted impression and reach reporting. We have confirmed that these issues impacted reporting only and not delivery” of statistics about Facebook pages.
While ad insights were not impacted by these problems, the company is fixing the bugs–possibly increasing your page statistics. Although Facebook “won’t be able to backfill Page Insights with historical data,” you will have a better idea of how many readers visit your page. Here’s more from Facebook:
Overall, we expect most Pages to see: Total reach to stay the same or increase for most Pages. An increase in paid reach if you ran News Feed ads. An increase or decrease in organic reach, depending on many factors such as the composition of your fan base, when and how often you post and your spending patterns. A change in metrics computed from reach and impressions, such as engagement rate and virality.