It's been 20 years since Harry Potter entered the imagination of children (and the young at heart). It all started with J.K. Rowling's Harry Potter and the Philosopher's Stone which was first published by Bloomsbury Publishing on 26 June 1997 in the UK. We've since sold over 40,000 Harry Potter products here at Mighty Ape!

To celebrate the 20th anniversary of the book that started a cultural phenomenon Bloomsbury have just released four House Editions of Harry Potter and the Philosopher's Sto­ne, and House Editions of Harry Potter and the Chamber of Secrets. These stunning editions each feature the individual House crest on the jacket, and line illustrations exclusive to that House, by Kate Greenaway Medal winner Levi Pinfold. Each book contains extra content including fact files and profiles of popular characters. The edges of each book have also been sprayed in the House colours, and are available in both hardback and paperback formats.

Fans can now choose the book that represents the House that they pledge allegiance to. Every Harry Potter fan has an opinion on which is the best House and could debate it for hours on end. Blogger Ani Bundel from WizardsandWhat­not.com recently ranked the Houses from best to worst as follows.

House ranks by WizardsandWhat­not.com:

1. Gryffindor
2. Hufflepuff
3. Ravenclaw
4. Slytherin

It's no surprise to see Gryffindor at the top of her list, and Slytherin at the bottom. However, despite their terrible reputation, we don't have any problem selling Slytherin merchandise at Mighty Ape. They may be looked upon by many unfavourably, but does that mean that they are the least popular? Which raises the question, which Hogwarts House is the most popular?

Money talks, so we used sales of the new Harry Potter and the Philosopher's Stone 20th Anniversary House Editions to see which house was most popular.

House popularity by sales of Harry Potter 20 Years House Editions:

1. Gryffindor (29%)
2. Slytherin (28%)
3. Ravenclaw (22%)
4. Hufflepuff (21%)

Since Friday June 2, when our Harry Potter 20 Years House Edition stock arrived, Gryffindor has held the lead. However, surprisingly Slytherin holds the second spot. It's pretty much neck and neck with Slythrin behind Gryffindor by just 1%.

This data was based on just one group of Harry Potter products, and less than a week's sales at the time of writing. We have much more data that we can draw from. So we had a look at the past three years' sales of Harry Potter products. Here's how the Hogwarts Houses stacked up.

House popularity by sales of Harry Potter products over 3 years:

1. Gryffindor (38%)
2. Slytherin (30%)
3. Hufflepuff (17%)
4. Ravenclaw (14%)

We can now say definitively that Gryffindor is the most popular house in Hogwarts. What many people may not have expected however is that Slytherin is the second most popular house. With third and forth place going to Hufflepuff and Ravenclaw respectively.

The Harry Potter 20 Years House Editions are available now.

Not sure which House you belong to? Pay a visit the Sorting Hat at Pottermore.