How old is this map?

Recently I moved to a new place, and we (my roommates and I) bought some furniture from the older tenants- a dining table, a sofa, storage cabinets, and desks and chairs. The desk I bought has a world map on it. A couple of days in, I noticed that the map featured the Soviet Union. This means that the map and thus the desk was from before 1991; now I knew the desk was old, but I hadn't imagined that it was this old. As it turned out it is even older.

There was some info on the Mercator projection and some copyright details, but no date. I wanted to find out how old the desk was, and thus I needed to find the date of the map. Lucky for me Randall Munroe already has made a solution for this.

I follow the flowchart, only to be stuck at the part about the capital of Micronesia. The map just wasn't detailed enough to indicate the cities on the tiny nation. I figured my way around it and found out eventually that the map infact belongs to the period from 1982 to 1984. However I wondered if there was anyway to modify the flowchart to incorporate the fact that answers to some of the questions may not be obvious from the map. That led to try and come up with a small JavaScript code that basically asks questions and based on the answers updates constantly the possible time periods the map may be from.

I basicaly mined the corresponding page from explain-xkcd.com, and made a list of the questions, the answers, and the time frame corresponding to those answers. Then I wrote a script which simply runs through the list and asks only those questions which have a potential to update the already established time frame. For instance, if we establish that the map is created after 1947, due to the existence of Pakistan, then questions such as "Does the United States exist?" are not asked since the time frame 1947+ is a subset of 1776+. I initially wanted to create a back button to update anwers without resetting the whole thing, but then I got bored and postponed it (most probably to never).

Find the age of a map...

You can have a demo at the link above [^] or look at the script code  , and let me know if there are any errors in the events or if you have any improvements for me.I tried the resulting script on various old maps, which you can find at Old Maps Online , and the it seemeed to work correctly! All that's left is to sit and enjoy my 35-year-old (probably) desk!