eMarketer has been forced to revise its Twitter growth forecast for the US, the company's home market. As the social network struggles to gain users around the world, eMarketer has revealed that due to almost stagnant growth over the last few months, it has reduced Twitter's estimated annual growth in the US from 8% to a lowly 2%. The research company has also changed its forecast for Twitter's next four years, reducing its forecasted user growth from 14 million new users by 2020, to just 3.6 million. It was also revealed that the US market share, which was previously expected to increase, is now forecast to actually decrease through until at least 2020. The report said that the decrease in market share was due to platforms such as Instagram growing faster than expected, damaging Twitter's growth.