The GETH client has 3 Blockchain sync modes (fast, full or light). The 'full' mode which we have used to produce the data chart below takes up the most amount of space as it stores all previous states. For the average user, running Geth with the synchmode 'fast' (the default option) will produce a ChainData folder size (around 12-15% the size of the full synch) that is significantly smaller and lighter. This dataset was produced using Geth 1.6.7 stable.
Tip: Check out the FAST Sync Chart!