I love playing with Legos. I love playing with data. So when I got a chance to play with Lego data, I had a ton of fun. I have seen analysis of Lego prices (this 2013 article on lego is my favorite), but I thought I might be able to do something different, with the most recent data.
Using the rebrickable database, for detailed set information, and a scrape of the brickset website, for retail prices, I created a dataset of real price per piece, that is I control for inflation. Like many people who have looked at Lego prices, the real price per piece does appear to be declining over time:
To dig further into the data I restricted my analysis to the last 10 years. Sorting the data by theme we see that the cheapest sets are the special holiday sets and themes with very large sets. I was surprised that the Modular Buildings were so cheap. Classic, makes sense because they are the most basic bricks, but the Modular Building theme typically has many specialty pieces.
Most of the highest priced themes are also not to surprising, the sets that have electrical circuitry are more expensive. I was surprised by Pirates and Space being so high up on the list though.
However, I wanted to have a little fun. The rebrickable dataset gives the inventory for each set, and their colors. Using the frequency of the color in each set I reweigh the price per piece by the frequency of color. The graph below shows the price by color for all the non-translucent pieces.
If we look at translucent colors, it does look as though, in general, those colors are slightly more expensive:
I can also break down price by individual piece and again the prices more or less follow expectations. Very small pieces are cheap, large pieces with electronics are more expensive.
So if your goal is to expand your lego collection, get those modular and classic sets, and enjoy your Lego builds!