How does population work and combating population decline

[Xavicious]

Overall the game is fairly easy. If you are having population problems I hope this helps.

This is my understanding of how the population works in game and how to prevent population decline.

The entire game is based around growth and decline. We need to understand this wave to really combat population decline. To me the design is pretty awesome, because there is little to no room for stagnation. This means the game is always a balancing act of growing or declining.

The base understanding is that your growth is based on the number of children you have at any given time. If the number of children is going down then you are in decline, otherwise you are in growth.

All of the following estimates do not include random deaths. When you have more deaths in your adult population, then your growth will slow down. My estimates are based on a entirely healthy population that die from old age. Out of control growth would actually be easier to manage if you can provide a controllable adult population death rate.

My estimates are based on the average maximum age of your adult population (adult meaning workers). When starting out without a school it seems to be around 5-6x the maximum number of adults to children. This means when you have 10 children, your target adult population would be between 50-60 population. Another way to put it is if you generated 10 children at a consistant rate for 6 generations, then you would have 6 generations of 10 people. With the exception that your growth (number of children) will never be constant because your children count will change with your population.

So why the decline?
The decline happens when your population has no open houses to keep up growth. The basic rule is that without a new home you will not create new couples to reproduce. This means you will need to be building housing at a consistant rate to be in growth. If you stop building houses then your population will go into decline. On the other hand, if you build too many houses then you will boost your children up too high and will have an uncontrolled growth.

Think of decline and growth as a single wave around a set population limit. Where decline is the bottom of your wave (minimum population) and growth is the top of your wave (maximum population). With small populations the decline low is less than 0. Meaning that your population will hit 0 and you will lose. Larger populations have the possibility of working themselves through a decline.

The game is programmed to make decline worse if you do nothing to fix the situation. I think these game rules are:
1. Couples only produce so many kids
2. Couples have less chance of reproducing as they age

Basically, older couples will "lock" a house from reproducing. This means that the other adults living in the home will not be able to reproduce. If you try to fix the situation too late with building houses, then you will have "older" couples move into the new homes. Older couples already have a lower probability of producing offspring, which means it will only slightly slow decline not reverse it. The later you wait to slow the decline, the less effective your results will be.

How to combat uncontrolled decline?
1. Build houses. You will need to build as many houses that you can get down to 1-2 adults a house. After your adult population start dieing off then you can remove some of these houses to decrease the growth after you have declined all the way.
2. Remove kids from school (remove adults from teacher jobs). It will increase your chances of producing offspring. My thought is that they will have a longer period to reproduce, meaning it will help counter the decline. Make sure when you remove these kids from school that they have houses to create a couple and move into.
3. If houses are still locked up then kill off some older adult population. If you can figure out a way to do it, then let me know. We really just need retirement homes for these folks.
4. Recruit nomads. Dont do this if your houses are still locked up. You need to increase your child count / reproduction to get out of decline. This is a uncontrolled growth approach.

I have sucessfully recovered from having 0 children for 5 years in one of my games by doing just the first 2 above.

Just accept that growth and decline are part of the game. You just need to manage it so that the peaks of the wave are not extreme. If your growth increases are huge amount, then you are bound to have a huge decline with it. Keep at it all at a steady rate. Patience seems to be a key element.

[D3vilkin]

This is awesome work you did there Xavicious! Thanks for the tips!

[Lurick]

From what I've noticed is that right up until they are around 40 to 45 they will generally have a good chance to produce kids. Any time after that and your chances of them having a kid are next to 0 and the limit on the number of kids seems to be 3, maybe 4 if you're lucky.

[Rune Vortex]

I completely agree with the above.

[ChewMyFudge]

Thought somebody said couples don't mate after 35 or something.. anyway, it's useful to always build houses so that your child birth is above 10 for a stable Town growth.. youngsters don't get together in their folk houses, so unless there is an empty one, you are missing out on population increase

[ArcaneGamer]

If you stagger your population growth with a proportionate number of children at all times, you can have a sustainable demographic: births matching deaths over a generation, eliminating the probability of a decline. The concept of building houses to prevent a demographic cliff really counts at the beginning! Otherwise, good planning, management and timing can prevent population decline without having to continuously expand with more housing. You invest too much in housing at any given time, and you will increase the possibility of severe shortages! You invest too little, your population will decline if not collapse during the first decades of your town!

[Patriot]

https://www.youtube.com/watch?v=FDx2NnrPxWU a good video tutorial for those that still need help.

[Brythones]

I've got alot of empty housing, is it better to get 2 'young' adults in one house as opposed to one?

[Brythones]

I managed to get Nomads by building a town hall, market and trading port (apperently these are required for them to come). I had to get rid of old people, hire young people in any profession apart from Builders (just keep spamming it until you get a young person as a worker in a specific profession ie, one young worker in each job with NO others in it), then, build a bridge to an empty island and order the old labourers to collect resources on the other side and destory the bridge, and then wait until they die in the island.

[Brythones]

Hello! After revising my work I've realised that it was due to a number of reasons, but, I've been looking into it, and I have calculated crop treads.
Don't worry - these are all correct now ! They apply to 'medium' difficulty.

Each 1x1 plot has a chance of churning out '5', '6' or '7' lots of food (depending on your luck), which applies to the whole field. Yearly, the total amount of food required by citizens is 100 food (yet this can sometimes be between 90 and 110. Each citizen can only 'hold' upto 120 food at any given time, so if no food is available then they will die within just over one year.
As far as I am aware, smaller plots give out the same as larger plots, yet, if they are worked enough (ie. a 4x4 plot with one worker) then you can receive dual harvests (this occurred to me several times) which max at '10'.

Assuming therefore, that conditions are terrible with each field producing '5' food and each citizen eats 110 food then you will need 22 plots per person, which would approximately a crop field of 4x6 for each citizen.
- I will finish this later :P

The average food production for fishing with 4 workers is 1200 food per year. This can vary between a minimum of 1000 and maximum of 1400, which is enough food for 9 people at minimal levels (the net value of this is 5 (ie. the number of people it will feed excluding those who produce it)).

[ArcaneGamer]

@ Britisher Excellent work*, but can you please fix all the grammatical errors so the text is easier to read.

*ab=c; 15(X People) = ~ Y Crop Size

It is rumored that [8 to 10]*15 crop size more efficiently yields a harvest.

[TucanSam]

Originally posted by Britisher:

I have come up with a simple measurement, namely the AFC index - this is abbreviated from Average Food Consumption. Under moderate conditions, the starting supply of food is 1800 with 15 citizens. We start in early spring. With all requirements - such as firewood and housing - statisfied, this supply runs out in around mid-Summer. This is approximately 1 & 1/2 seasons which encompasses 37.5% of the year.
Within this time, the AFC was 120 per capita, thus the AFC per capita per annum is 320.
This means, yearly, you're aiming to get 320 food per citizen you have or - preferably - above.

I then worked out the food value per harvest (this is an annual rate) of crops in any 1x1 square. The result was 25.5 per square (which has room for error due to the fact that harvests are random), so I chose to make it 25! This means each 1x1 square, should in theory produce 25 food - meaning each citizen would need 12.8 squares to survive per year (I rounded this up to 13). Quite neatly, this maths equation which would be 13 x 15, would require a crop field of this same size (13x15).

So here's a simple method to keep your population alive: Begin the game with a 15x15 crop field (this allows room for error) or 15x13 if you really want to "risk" it (this should be statisfactory as my rounding has allowed for an excess production of food).
Each house can contain upto 8 people. Therefore, for each house you build, build a 8x15 crop field (or any field(s) which encompass 120 or more spaces). This does seem like a large amount, yet this is solely on crops and does not consider other methods of food production, and it is at maximum housing capsity.
Note: under this equation assumes that crop field has a sufficient level of employment, and that each harvest is successful - this does not consider whithering during the winter months (which can be combatted by employing as many villagers as possible as farmers) or crop infestation.

Another simple way of remembering this is that, you make [Number of People]x15 crop field size, so if you have four people then it would be 4x15, five would be 5x15, six would be 6x15 etc.

It is actually better to start with a food source other than a farm, as they only produce in the off-season as well

[Brythones]

Originally posted by Knight Lazarus:

@ Britisher Excellent work*, but can you please fix all the grammatical errors so the text is easier to read.

*ab=c; 15(X People) = ~ Y Crop Size

It is rumored that [8 to 10]*15 crop size more efficiently yields a harvest.

I think I've fixed most grammatical error but some terms might be slightly complex. I think I will change the set-up of the post later, at the moment I'm working out the food production of fish and if you are right in saying that larger crop fields are more efficient!

[Maverick]

Originally posted by Britisher:

I have come up with a simple measurement, namely the AFC index, or the Average Food Consumption index.

All this would be well and good numbers IFF people ALSO have 100% guaranteed ACCESS - with ZERO variability.

Unfortunately Banished doesn't work this way and most people lose their towns regardless of this "AFC" for OTHER reasons.

So here's a simple method to keep your population alive

So where's the firewood AFC? Where's the tools ATC? Where's the coats ACC?

And you cannot start a new town with a 15 x 15 crop if you play on hard either. NOR should you start with a reliance on crops before you have population spare to tend fields - without interruption - and a quality off-season capability (as tucan said).

As an aside, what's your biggest population? IS it rude to ask that you back up "THIS is how you do it" with some numbers?

[Staber13857]

fyi
you want a farmer for every fifty crop squares minimum.
you want a farmer for every 40 if the crop is a later one because an early frost can screw you alot (the plants degerate very quickly if you didn't notice).
a lone farmer can actually work 70 orchard tills pretty well but the orchard itself is time conssuming early game and can be.... unreliable at times production wise.

[Brythones]

Originally posted by Maverick:

Originally posted by Britisher:

I have come up with a simple measurement, namely the AFC index, or the Average Food Consumption index.

All this would be well and good numbers IFF people ALSO have 100% guaranteed ACCESS - with ZERO variability.

Unfortunately Banished doesn't work this way and most people lose their towns regardless of this "AFC" for OTHER reasons.

So here's a simple method to keep your population alive

So where's the firewood AFC? Where's the tools ATC? Where's the coats ACC?

And you cannot start a new town with a 15 x 15 crop if you play on hard either. NOR should you start with a reliance on crops before you have population spare to tend fields - without interruption - and a quality off-season capability (as tucan said).

As an aside, what's your biggest population? IS it rude to ask that you back up "THIS is how you do it" with some numbers?

It was more of a guide for those who cannot get food production right, and yes, it is about numbers as I've been looking into it and (in moderate conditions) there are certain, fixed rates of crop return (ie. you can only get a harvest which is between a fixed level of values each year) in place for ideal crop fields. I only wrote that yesterday, so if you want any other indexs you are more than welcome to work them out yourself. And I stated that it was done in moderate conditions / medium mode. I'm working on fish and crops at the moment, and I'll fix my post later today.