Quandl Open Data
Quandl is a Toronto-based website that aims to be a search engine for numeric data. Unlike most search engines, however, its database isn’t automatically generated by spiders that crawl the web. Rather, it focuses on linked data that’s updated via crowdsourcing — updated manually via human curators, in other words.
Because most financial data is in numeric format, Quandl is an excellent tool for staying up to date on the latest business informatics. As you can see, a search for Apple returns over 4,700 datasets from 11 different sources with time series at the daily, weekly, monthly, quarterly, or annual level. Many of these results are related to the United Nations’ agricultural data. If you’re looking for data on Apple Computers, you can narrow the scope of your search by replacing the Apple search term with the company’s stock abbreviation AAPL.
The Quandl database includes links to over 10 million datasets (although they use a generous metric in declaring what distinguishes one dataset from another). Quandl links to 2.1 million UN datasets and many other sources, including datasets in the Open Financial Data Project, the central banks, real estate organizations, and well-known think tanks.
You can browse Quandl data and get instant charts based on what you find. If you sign up for a free registered account, then you can download as much data as you want or use the Quandl application programming interface (API). The Quandl API includes wrappers to accommodate platforms such as Java, Python, Julia, R, MATLAB, Excel, and Stata, among others.