Writing task 1

I have written an IELTS essay and I really need someone who can check it for me. I will be greatful so much.

P/s: My essay not only has grammar mistakes, it is also too long. ??????? Can you give me some advices to make it shorter and more simple?

The table gives the figures for congestion by size of one country's population from 1995 to 2015 as indicated by the average delay experience by travelers. In addition, there is a sixth category which shows predicted figures. The survey was taken every ten years, so the changes in the survey results can be compared over time.

Overall, the largest increase in delays occurred in the period from 1985 to 1995. And between 2005 and 2015 it showed a decrease. In fact, the smaller cities have shorter delays per person than the bigger one.

First of all, the small cities of under 500.000 people had the most notably change, with having 7 delayed hours per person in 1985 and climbing for 21 hours only after ten years. This all happened in different-sized cities. The longest delays happened in 2005. The mega cities even reached at 60 hours' delay experienced.

However, in 2015, a traveller from both medium and small cities average experienced 21 delayed hours, which was shorter than that in 2005. All categories of city will experience shorter delays in the future but to varying degrees. Medium cities (those with 500.000 to 1 million inhabitants) is forecast to be 15 hours in congestion, much smaller than in 2015 by 6 hours.