It's still growing, but not exactly skyrocketing anymore: "The highest global population growth rates, with increases of over 1.8% per year, occurred between 1955 and 1975—peaking to 2.1% between 1965 and 1970. The growth rate declined to 1.2% between 2010 and 2015 and is projected to decline further in the course of the 21st century."

You need to look at people dieing as well. Most of the population in those countries with high growth is really young and won't die for many decades. If they have an amount of kids below the stasis limit these kids will be alive at the same time and if the kids are more than the grandparents during the total population will go up to a while.