It's an old "feature" of WP.
It's not missing. You'll be able to find them using IE or any other browser (on the phone or PC) to access your account or using an Android/iPhone.
How MS expects corporate people to adopt WP without beings able to show older than 2 weeks/over than 6 months in the future appointments, I don't really know.
What I did was going to my Google Agenda (my case) on IE on the phone and pin it to my Start screen.
Enviado via Note 4