It depends on what type of report you are writing. If you are writing an argumentative or informative report, it is essential to include facts and evidence to support your topic. In these kinds of papers, you can also use your opinion, but you can only use 3rd person pronouns. Whereas if you were writing a persuasive report, then you would use more of your opinion on the topic you were trying to cover. (All of this comes from my VERY smart Advanced English teacher... so it’s reliable!) Hope it helps!
Answer:
it might be at least more than 20 year
