Hi,
In less than 20 years from then, the number of mobile phone subscribers is over 42million. In the diffusion rate, it’s 87.7%.
->Please check if this sentence is awkward. I really don't know how to write the second sentence. 'in the diffusion rate' part.
I'd say In less than 20 years, the number of mobile-phone subscribers has grown to more than 42 million. The diffusion rate is 87.7%.
Best wishes, Clive