A colleague said to me “Everyone is running on fumes with Easter being so late this year.”
Really? Is it late? I admit to being completely perplexed by this religious date and its movement around the calendar. I always feel like I am the last to know when it is, let alone whether it is early or late.
Let’s have a look at what constitutes an early or a late Easter. The data are available here.
This is a quick post with no code example (sorry). I figured the best way to visualise the data is to use a histogram-style representation with years being colour coded.

The image above shows the frequency of Easter Sunday dates from 1600-2099.
So, pretty much Easter tends to be between 25th March and 22nd April. This year, 2022, Easter Sunday is on April 17th and it is indeed quite late. There are a few high frequency dates March 31st, April 5th, 11th and 16th, and some low frequency dates March 28th and April 9th as well as March 25th and earlier, April 23rd and later. Funnily enough next year, it falls on April 9th, one of these dates.
The internet says: the date for Easter Sunday is usually the first Sunday after the first Full Moon on or after the March equinox. And there is some jiggery pokery around different calendars. But this explains a) the date range and b) why it moves around since it relates to the lunar cycle and the annual calendar.

What’s not so obvious from the first plot is that the date of Easter Sunday oscillates by year, as shown in the image above. Generally speaking, a late Easter is followed by an earlier one, and vice versa. This rule of thumb can be useful as a bluffer’s guide to Easter.
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The post title comes from the album Easter Everywhere by 13th Floor Elevators. I love the opening track “Slip Inside This House” which is a microcosm of the band’s sound. It was later covered by Primal Scream on their Screamadelica LP.