If you have been manually updating the year on your websites/app footer like this folks, you've been doing it wrong...
Screenshots taken Sunday 13th, January 2019
And I'm sure there's plenty more so either don't include it at all or do it programmatically!
Here's a few examples of how you could achieve it :
JavaScript
<script>document.write(new Date().getFullYear());</script>
PHP
<?php echo date("Y"); ?>
Python
import datetime as dt
{{ dt.datetime.now().year }}
Ruby
<%= Date.today.year %>
Now go update your website and let fellow developers know about this simple workaround!