By Katherine NoyesThe virtual ink had barely dried on our Table of Estimated Subscription Revenues last week when the Financial Times published results indicating an even more successful year than we had estimated for the company. Most notably? For the first time, the publication’s digital content revenues exceeded print content revenues in 2013.Not only did the Financial Times Group achieve profits of £55 million — marking an underlying increase of 17% year-on-year — but FT’s total circulation grew 8% year-on-year to 652,000 across print and online, representing the largest paying readership in the publication’s 126-year history.Perhaps the best part, however, is that FT.com digital subscriptions grew 31% to 415,000 — we had estimated 400,000 in our 2013 Online Subscription Benchmark Report — representing almost two-thirds of the FT’s total paying audience. Corporate users grew nearly 60% to more than 260,000. The result “more than offset” planned reductions in print circulation, FT said.Also interesting is the growing importance of mobile to FT’s results. In 2013, in fact, mobile drove 62% of subscriber consumption, 45% of total traffic and almost a quarter of new digital subscriptions. The FT’s flagship web app now has more than 5 million users, and new apps on Google Newsstand and Flipboard have further added to FT’s mobile presence.FastFT — FT’s 24-hour news service — helped to significantly increase overall digital engagement as well, FT said, as did mobile-app redesigns and improvements to FT.com.The bottom line: Digital and services revenues accounted for 55% of FT Group revenues in 2013 — compared with just 31% in 2008 — while content revenues grew from 48% of revenues in 2008 to a full 63% in 2013. (Note that FT didn’t define content revenues; we assume they refer to subscription revenues, but they may include ancillary revenues from sponsored content or one-off sales.) Advertising, meanwhile, is down to 37% of FT Group revenues from 52% in 2008.