Hi Amril,
Nice to see your essay here. Your essay is great, but let me try to comment on your essay.
Your, overview, I guess, it was too complex. You need at least 2 sentences to highlight and than put on your body paragraphs. Maybe, you can choose a similar trend showed an gradual increase generally and Germany as the largest expenditure.
You should divide your explanation with proper body paragraphs by grouping, it will make your flow better to read. Perhaps, you can use years for separating the essay. for example, 1995 and 2005 will became one paragraph in body 1, then others are in body 2. second option, 1995 - 1999 for one group, and others for else group.
And, you should use comparative sentences, such as slightly larger, considerably the greatest spending, gradual less expenditure, these words will enhance your essay. So, your readers will not feel bored with same pattern.
A comparison of changes in the amount of money spent on books over a 10-year period(or you can use : over the period in question) , which is measured in usUS dollars in four countries(i guess you forgot it) is depicted in the line graph
I hope it can helps, good luck then :)