Population Growth

[Gareth_Perkins]

The campaign I'm currently moderating has a healthy dose of exploration-and-colonisation about it,

All of my players are running extremely tight for census (even with the rapid-colonisation rules in effect), indeed, census is proving to be much more valuable than EP (most of the players have no real financial problems at the moment, even with the massive hike in raiding due to some horrifying events),

So one of my players has hit upon the idea of "relocating" chunks of census towards the end of the year in order to maximise his chances of gaining the maximum possible number of census increases, and then relocating them again to produce EP...

It will cost him in EP every year, but he's not too bothered about that - it's the extra census that's important,

Now this strikes me as very artificial, but is at it's heart a outward symptom of some of the inherent problems with the current system of population growth (along with the fact that ten 1 census systems will all tend to "pop" at the same time, while population growth should be somewhat more constant). A bit more thinking gave me the following (much simpler, and easier to keep track of) idea:

At the end of a year, instead of the normal growth die rolls, divide your Empires total population by a "Growth Ratio" . The result (rounding down) is the number of extra census gained across your empire this year, these points should be allocated one at a time to the system with the largest census and working down (in the unlikely event of running out of systems, then start again from the top). Any remainder (from the calculation) is added onto your census next year when figuring your growth.

e.g.: I have three planets with populations, using Growth Ratio 10:
Planet A: 8 Census
Planet B: 4 census
Planet C: 3 census
At the year end I have 15 total census, so my growth is 15/10 = 1 census, which gets added to planet A (as it has the highest current census). I also have a remainder of 5 points to carry over to next year.
At the end of the next year (assuming no other changes) I have 16 total census, and 5 remainder for a total of 21. 21/10 = 2 new census (assigned to planets A and B), and a remainder of 1 for the next year.

There are a couple of oddities about this system too - notably the lack of growth on low-census systems. This first can be explained away as very poor growth and movement of populations towards "civilised" planets (think of movement of people from the countryside into the cities). Alternatively a weighted roll could be used to determine where the new census appears.

If you want a random element (and I'm not sure it's necessary) then you could consider adding 2D10- (roll 2 ten sided die, subtract the smaller roll from the larger) to the total each year (you may want to increase the growth ratio by a point or two if you do this).

If you want to you could do monthly growth instead of yearly to keep track of variations in population across a year - just multiply the Growth ratio by 12 (you will probably also want to use the weighted roll to see where the census appears if you do so).

If you want to use the slow population growth rules, then simply double the growth ratio (Growth ratio 10 will give 10% yearly growth, 20 will give 5% yearly growth, etc).

Races with rapid or slow procreation can be represented by simply varying the growth ratio - a fast breeding race might use a ratio of 2/3 the scenario value, and a slow-breeding race might use 1 1/3 of the scenario value - you could even allow multiples of these traits to stack.

Finally if you are using the Climate ratings rules, you could "weight" each census point when determining growth. Census on worlds with climate variance of 2 or less could count at full value. Census on worlds with climate variance of 3-5 could count at 50% and climate variance of 6+ could count at 25%,

Any thoughts?

[Charles Lewis]

Somewhere in the past, I posted some possible Frontier Population growth rules. Essentially, you checked every six months for any colony with a population of 3 or less [or maybe it was just less than 3 - I can't remember for sure off the top of my head] (and accumulated those modifieres to subsequent die rolls). The result is a quick and straightforward process to stimulate the likely enhanced emigration to new colonies on top of any organized efforts by the government.

Your system would work, but does not necessarily reflect the "frontier" mentality that would be present in a population with access to new opportunities. New colonies also represent new avenues for those in the established areas but lacking in opportunities for upward growth.

[Gareth_Perkins]

True,

You could flip it around easily enough and place the census on low census planets first though,

My assumption was that after the initial influx of residents (represented by the colony fleet arriving and depositing what is after all a lot of colonists - one census is equivelent to one twelth of the maximum population on an Earth-like planet after all! - perhaps half a billion colonists!) a lot of younger folks upon leaving home are likely to want to "leave home and go to the big city" so to speak,

I also wanted to avoid a situation where I was rolling for every system every year (and tracking each systems modifiers across years)...

[Chyll]

Your system makes sense over all, Gareth, and I have run into similar issues occasionally. I have never used Charlie's rule, but remember liking it when I saw it in the past...

On the other hand, avoiding taking the census value quite so literally.

one census is equivelent to one twelth of the maximum population on an Earth-like planet after all! - perhaps half a billion colonists!)

If anything it is probably geometric and not a linear representation.

I try not to consider it to represent a hard 'count' of people but a general indicator of contribution from the population involved towards the capacity/productivity.

[Gareth_Perkins]

Your system makes sense over all, Gareth, and I have run
If anything it is probably geometric and not a linear representation.

I try not to consider it to represent a hard 'count' of people but a general indicator of contribution from the population involved towards the capacity/productivity.

Hmmm,

It would make sense, but it puts lie to the way census is moved around... If the first census point is 1,000 colonists and the tenth is 1,000,000,000 then how come they occupy the same cargo space And where do the extra poeple come from (or go to) when they make planetfall in a system with a drastically different census to the one they came from...

However, if so then the "growth" happening on the low census worlds first would make most sense, as the "growth" needed to 'pop' an extra census on these worlds would be much less significant when taken on an empire-wide scale than an extra census growth on a high-census world, and could in that case be taken as extra immigration,

So, on that basis I would suggest replacing the section above on census placement with something like this:

New Census should be allocated one at a time to the system with the lowest census and working upwards. In the case of a tie simply randomise the system recieving the census (In the unlikely event of running out of systems, then start again from the bottom).

[Tyrel Lohr]

I like the concept behind this, Gareth. I have not run into any major problems with the current population growth rules -- except for the obvious limitation of never having enough new Census to go everywhere you want to go -- but I can definitely see where you are coming from.

This solution would be a real time saver in larger campaigns where each major empire could control a dozen or more star systems or colonies. Being able to run a single calculation versus multiple population growth checks would reduce the CM's burden of the last turn of each campaign year.

I am divided as to whether the new population should go to old colonies (high Census) or new colonies (low Census). The geometric nature of Census parity to real world numbers would lean towards me saying the least populated colonies should receive Census first, but placing Census at the most populous worlds also makes sense simply because there are more people there, and a larger percentage may be ready to move to another system to start new lives elsewhere.

One downside I do see to these population growth rules is that they don't provide any bonuses for having a large number of colonies. You could control six star systems, but an opposing power with two and the same amount of Census would experience the exact same amount of population growth. Now, that is not to say that is a *bad* thing, but I do like how it is now that players have a reason to go out exploring and colonizing their little hearts out.

As for colony worlds all tending 'to "pop" at the same time', you must have a lot better die rolls than I do! I have had homeworlds go years without population growth just because of crummy die rolls. With average results they should all be fairly reliable, though, as you point out -- but I am cursed, and for some reason it never works that way for me!

As an aside, but related to population growth, for the last two years or so I have been using Climate Variance as a modifier to population growth. For every 5 points of Climate Variance or portion thereof, a colony receives a -1 population check modifier. Hostile environment planets instead receive a flat -3 modifier. This slows population growth at untenable colonies, while promoting higher population growth at more habitable planets.

[zyffyr]

My personal preference to deal with "lets move them around for a better growth bonus" types would be to use the average census since the last check instead of the census at the moment of the check.

[Gareth_Perkins]

My personal preference to deal with "lets move them around for a better growth bonus" types would be to use the average census since the last check instead of the census at the moment of the check.

You are right, this will prevent my players from finessing the situation, but it won't deal with the percieved problem - it's also lot of extra calculation that ultimately I'd rather not bother with... I know - lazy me

As for colony worlds all tending 'to "pop" at the same time', you must have a lot better die rolls than I do! I have had homeworlds go years without population growth just because of crummy die rolls. Confused With average results they should all be fairly reliable, though, as you point out -- but I am cursed, and for some reason it never works that way for me!

Bad luck will group the growth sometimes too

In the early game players tend to populate a lot of systems quite quickly with low populations (well, they do with rapid colonisation on anyway!). These systems will tend to sit idle for 7-8 years and then all will tend to 'pop' within a few years of each other. Then rinse-wash-repeat as their growth modifier resets...

From the point of view of a single planet this sort of makes sense (as you expect the systems census to gradually rise until it reaches the threshold for the next census level). But from an Empire-wide perspective it means that your total population will tend to be pretty constant for a while and then "hop". This is slightly less plausible - these numbers "caught in the rounding" so to speak potentially represent a lot of people!

Lastly, (ignoring the real world for a second) to make the game run more smoothly I figure a smoother population growth curve makes for a better game (I'd rather my players slowly gained census over gaining few census for ten years then rapidly gain half a dozen or more), this way they can slowly utilise the population and their empire is less likely to stagnate for long periods while they wait for their populations to breed!

[jygro]

I had an idea for ever-expanding population growth here: http://forums.vbamgames.com/viewtopic.php?t=182 but the more I think about my idea, I like the idea you are getting at a lot better. A single quick calculation based on the number of census, a empire's growth rate and a colony modifier might be a simple way of determining the growth of the population instead of calculating the population growth on every colony (and dealing with hundredths of census - yuck).

I think the number of colonies, the climate variance of those colonies, the total number of census of the empire and empire's growth rate should be factored into the calculation if possible.

I'm also torn between who gets the new census. I can see both sides of the coin. If I had to choose, I think I'd put it on the higher colonies and make the empire in question use colony fleets to ship them to the other planets. Of course, a second way of handling it, is to put the newly acquired census on the planets with the lower climate variance first.

Must think about this more...
-Bren

[Gareth_Perkins]

Hmmm, I'm not sure that I'm entirely a fan of "more colonies means more colonists", but I guess it does give the players some incentive to expand - which is a good thing.

A quick-and-dirty fix might be to simply add in the total number of colonies each turn, which will give players incentive to have a couple of big colonies (for the industrial capacity, and supply), some medium census worlds (for supply points), and a lot of low-census worlds (to maximise census production). Not the best result, but certainly better,

So, to summarise, that would make it:

(# of Colonies + Total Census + Remainder) / Growth Ratio = # of new colonists

Climate variance:
0-4: Treat census on these worlds at 100%
5-9: Treat census on these worlds at 50% (also Hostile worlds)
10+: Treat census on these worlds at 25%

Given the growth rate in the CG a basic Growth Ration should be about 22 (a census 10 world expands every two years on average, according to the CG),

Growth Ratio Modifiers:
Slow Growth: 200%
Fast Breeders: 66% (round down)
Slow Breeders: 133% (round up)

New Colonists Placement???

[murtalianconfederacy]

Hows about this:

Calculate the total census, then multiply it by 2/3, and add the number of colonies.

In the terms of the OP, with three colonies, 15 census and a Growth Ratio of 10:

(15x2/3)+3=13. 13/10 yields one census.

It would promote more colonies, but also ensure that Census is the primary determiner.

Lets say that an empire, the Cnidarilan Expanse, has seven colonies. One is the homeworld, two are standard major colonies, one standard minor colony and three standard outposts. This means that there are 33 Census.

Plug that into the formula, and you get a total Growth Determiner (the term for the census plus the colonies) of 29. With a GR of 10, this means that 2 census have been added to the Expanse.

Now, for a way to determine where the census goes, perhaps there could be something weighted towards the available space. Think about London. Its the capital of the UK yet people are moving away from it. Why? Well, higher prices are one factor, but another is room. And the frontier mentality would apply more to a major colony system with two census there than a major colony that has nine census. So instead of taking the census value, take the (capacity-census) to weight the random distribution of the census

[jygro]

This is what I've gotten so far, but I haven't thought about the climate variance of hostile planets (I guess it would technically be 20)

Each planet creates a population growth equal to:
Census on the planet ^ 0.6 x 10 x (1-Climate Variance/100)

The sums of the population growth x 2d6+growth rate/10 = number of census that turn.

So an empire with the following (see TLADIS):
Planet 1: Census: 11, CV: 0 (homeworld)
Planet 2: Census: 5, CV: 22 (barren)
Planet 3: Census: 1 CV: 14 (Adaptable)
Planet 4: Census: 1 CV: 21 (Adaptable)

So, the total pop. growth is: 42+20+9+8 =79

Edit: Population growth is multiplied by 2d6 + growth rate (between 2 & 12) and divided by 10. For every 100 points, a census is created. The remainder is added to next value.

Example: If the above empire had a growth rate of 7 and a 10 was rolled, the calculation would be: 79*17/10 = 134. 1 new census would be created and the 34 would be added to the next year's total.

In my testing. An empire that had 7 colonies with 32 census 'generated' 1.7 census per year. An empire that had 3 colonies with 32 census 'generated' only 1.1 census per year.

-Bren

[Chyll]

Your system makes sense over all, Gareth, and I have run
If anything it is probably geometric and not a linear representation.

I try not to consider it to represent a hard 'count' of people but a general indicator of contribution from the population involved towards the capacity/productivity.

Hmmm,

It would make sense, but it puts lie to the way census is moved around... If the first census point is 1,000 colonists and the tenth is 1,000,000,000 then how come they occupy the same cargo space And where do the extra poeple come from (or go to) when they make planetfall in a system with a drastically different census to the one they came from...

OK, a point to you there.
I guess my abstraction had allowed me to skip right past that issue.

I'd argue that it is still modeled in the contribution from the population involved towards the capacity/productivity. It isn't a count of people, its a count of what that population produces to the greater good of the empire. Lots of activity, production, and fervor is lost in the 'civilian' economy and the general hub-bub of the colony and you never get to benefit.

Anyway, murtalian's suggestion seems pretty clean, though it doesn't account for climate.