From 30th Jan 2015, Google Earth Pro has been made available for free, earlier it was $400 per year. In order to get a free license key you may click here and download Earth Pro today. As compared to the normal free version, it allows the following additional functions:

• Advanced Measurements: Measure land with polygon area measure, or determine affected radius with circle measure.
• High-resolution printing: Print Images up to 4800×3200 px resolution.
• Exclusive Pro data layers: Demographics, parcels, and traffic count for US only
• Spreadsheet Import: Import up to 2500 addresses at a time, assigning placemarks and style templates in bulk.
• GIS import: Visualize ESRI shapefiles (.shp) and MapInfo (.tab) files.
• Movie-Maker: Export Windows Media and Quicktime HD movies, up to 1920×1080 resolution.

A comparative analysis of Free and Pro functions is given below: