Story from Statistics: Demographics

I like to generate plot ideas and stories from known statistics about my various worlds. I hope to make this a series of posts on how exactly to do this.

Your players are entering a town they know nothing about. Who is inside this town? What do they have to offer? This town was a living, breathing place before the PCs got there, and it should react to them arriving.

Let's start with some numbers. I like to say that 2% of the world at large is "leveled" (that is, has at least one level in a character class). You can choose whatever number you want, or have it vary from region to region. My frontier regions have 3 or 4% of the population being leveled.

The classes are not made equal. Certain classes are rarer, or more difficult to train in. I use ten classes: Assassin, Bard, Cleric, Fighter, Mage, Monk, Mystic, Paladin, Scout, and Thief. I argue that the Monk is the rarest class, so we'll assign a relative frequency of 1. I'll say there are twice as many Mystics, Assassins, and Paladins as monks, so they get the value of 2, and so on up through to the most common classes, Fighter and Thief. Here are my numbers, and the consequent percentages:

Monk: 1 --> 3.226%

Assassin: 2 --> 6.452%

Mystic: 2 --> 6.452%

Paladin: 2 --> 6.452%

Bard: 3 --> 9.677%

Mage: 3 --> 9.677%

Scout: 4 --> 12.903%

Cleric: 4 --> 12.903%

Fighter: 5 --> 16.129%

Thief: 5 --> 16.129%

So, of a given population, 2% are leveled, and 16.129% are Fighters. Therefore, we have a good approximate number of Fighters for ANY given town, city, region, or country.

Let's get deeper. I would suggest that of a given pool of Fighters, 1/2 of them are level 1, 1/4 are level 2, 1/8 are level 3, 1/16 are level 4, and so on, each level containing about half the number of the previous level.

Let's create a large town of 10,000 people. There are 200 leveled people. There are 25.806 Clerics. There are 12.903 first level Clerics, 6.4515 second level Clerics, 3.22575 third level Clerics, 1.612875 fourth level Clerics, 0.8064375 fifth level Clerics, 0.40321875 sixth level Clerics, 0.201609375 seventh level Clerics, 0.1008046875 eighth level Clerics, 0.05040234375 ninth level Clerics, and 0.02520117187 tenth level Clerics.

Obviously, we can't have a .0252 of a person. So, read these decimals as chances of an additional member. 12.903 first level Clerics means there is a 90.3% chance of there being a thirteenth first level Cleric in the municipality. By the same stroke, .1008 eighth level Clerics means there is only a 10% chance of there being an eighth level Cleric at all.

Let's roll some dice and get exact numbers. We could roll for members of higher than tenth level, of course, but for the sake of demonstration I'll stop there.

1st: 13

2nd: 7

3rd: 3

4th: 2

5th: 0

6th: 1

7th: 0

8th: 1

9th: 0

10th: 0

We estimated in the beginning that there were 25.8 Clerics, and we got 27, a bit more than average. Furthermore, out town has the rare honor of hosting an 8th level cleric, which only 1 in 10 towns of its size can boast.

I have a google spreadsheet that calculates all of these instantly for me, but rolling a lot of d% will work just as well. After repeating this process for all the classes, we have definitive numbers of all the important players in the town. I like to say that anyone of 5th level or more is a "known" entity. They hold some sway in the community. From my excel sheet, I can make the following list of "important" people:

Assassins: One 5th level and one 8th level.

Bards: One 5th level and one 6th level.

Clerics: One 6th level and one 8th level.

Fighters: One 5th, one 7th, one 8th.

Mages: none (higher than 4th level, that is)

Monks: One 7th.

Mystics: One 5th.

Paladins: One 5th, one 6th.

Scouts: One 5th, one 7th.

Thieves: One 5th.

We now know have a list of the 16 most influential people in the town. Do you see the possibilities? Who are the PCs competing with? Which of these people are looking for recruits? Who hates who? This town has three 8th level NPCs! What does that mean? Were they once an adventuring party themselves? Monks are the rarest class, yet by chance we rolled a 7th level one. Who is this person?

This is where story lies. It is contained within a world that exists independently of the PCs, which has its own rhyme and reason that the players can tap into. These numbers scream tales to me, they whisper to me about adventure opportunities, they seem to invent histories for these people.

Don't shy away from numbers. They'll do so much work for you, they'll surprise you, and they'll hook together in ways that will withstand the closest scrutiny.