The Triangle has exploded in population since I first worked here on the railroad back in the mid-1980s. Raleigh-Durham was once an MSA, but was split into two separate MSAs at least by 2010. Back in the 1980 United States Census, the Raleigh-Durham MSA was comprised of only 3 counties (Wake, Durham and Orange) had a population of 635,008. In the most recent United States Census, the Raleigh-Cary MSA had a population of 1,413,982 and the Durham-Chapel Hill MSA had a population of 649,903. The Raleigh-Durham-Chapel Hill CMSA has grown to include 9 counties (adding Johnston, Franklin, Vance and Lee to the Raleigh MSA; adding Chatham, Person and Granville to the Durham MSA), for a combined total of 2,106,463 (includes the Henderson μSA, ergo Vance County). That is a 224% increase since 1980.
Jumping up to July, 2022: Raleigh-Cary comes in at 1,489,947 and Durham-Chapel Hill 670,863. Adding in Vance County (42,051), we get a derived total for the Raleigh-Durham-Chapel Hill CMSA of 2,202,861. That's a 4.5% increase in just a little over 2 years and 247% increase since 1980.