"Its first million articles took five years to put together, but the second was achieved just 12 months later." "... helped the site reach the 2m article miles

"Its first million articles took five years to put together, but the second was achieved just 12 months later." "... helped the site reach the 2m article milestone just 17 months after breaking the 1m barrier ..." From the other numbers in the article 17 months seems right.