Sunday, August 15, 2010

World Building: Macro-economics (Part 2)


This post is a dump of fairly raw data on the amount of goods produced by a manor.
This data is meant to be scaled up to the province level, not detailed down to Harn-like granularity. My long term aim is to create price indexes for a few broad ranges of goods from which I can derive prices for items on the equipment lists and for trade should the player wish to try their hands as merchants. The information here will be used to set the production values of the base index.

The manor produces Food, Metals, Raw Textiles and Timber and exports these items to local urban centers where they are consumed or worked by craftsmen into manufactured products. These are the average amounts produced per manor, not every manor's output will be strictly as described below. In a small barony of five manors there may be only one mining operation which produces 1500 lbs of metal per year and no mining at all in the other manors.

Amount of Food:
  • 1 acre produces on average 500 lbs of foods per year.
  • A person consumes about 5 lbs of food per day.
  • 20 acres supports 1 family adult and dependents with 10000 lbs of food per year or 5 tons. (Includes feed and seed.)
  • A manor of 100 feeds 50 city families which is 500000 lbs of food per year or 250 tons.
  • This food is produced on 3000 acres.
  • Includes grains, meat, grapes, milk, fruit, etc.
Amount of Metal:
  • Iron produced at 3 pounds per capita per year.
  • A manor of 100 produces 300 pounds per year.
  • This is mostly iron but can include gold, silver, copper, tin, zinc, etc.
Amount of Textiles, Furs, Hides:
  • Linen from flax.
Flax 1000 lbs per acre of which there is spinable flax for 25 yards of linen.
5 yards per outfit.
Acres of flax per manor = 10% of 3000 = 300 acres which produces 150 tones per year or 7500 yards of linen or 1500 outfits.
  • Leather
Pigskin is common.
10' sq per pig.
400 pigs per manor, 25% butchered a year.
50 lbs of meat per pig
5000 pounds of meat per year or 2.25 tons (as apart of total food)
1000' sq feet pigskin or ~100 yards of leather, 20 outfits.

Cowskin from naturally loses only, i.e. 10% of herd.
Herd of 100 cattle.
40' sq feet per cow
400' sq ft leather per year
~45 yards of leather or 9 outfits

Deer, Elk
Hunt 50 a year
20' sq feet per animal
1000' sq feet deerskin or ~100 yards of leather, 20 outfits.

200 sheep per manor, 10% loses
5' sq ft leather
10 lbs of fleece per year, 15 yards of wool or 3 outfits
2000 lbs of wool per year or 1 ton or 3000 yards or 600 outfits
100' sq ft or 9 yards or 2 outfits

  • Furs (beaver, rabbit, fox, ermine, etc)
Hunt 50 per year
~4' sq ft furs
20 yards per year

Amount of Timber:
  • 200 trees per acre, 30' tall 10" diameter, 500 lbs. or 100 tons per acre total.
  • Sustained harvest at 10% = 20 trees weighing 10000 lbs. or 5 tons.
  • 200' board feet per ton. (Board feet 144" cubed.) 10' 2"*4" is 960' cu. is 6.66 board feet.
  • 10' by 10' wooden wall (30 2*4s) is 200 board feet.
  • Acres of timber per manor = 10% of 3000 = 300 acres which produces 1500 tones per year.
  • A 20' by 30' for wooden house requires 22 tons of raw timber.
  • 1 urban family burns 20 tons of wood as fuel per year reducing available timber to 500 tons per year.
  • Building upkeep for 100 dwellings reduces available timber by 200 tons.
  • 300 tons of timber available per year.
Total yearly exports of a manor:
  • Food: 250 tons (Mostly grains, some meat, fish)
  • Metal: 300 lbs (Mostly iron)
  • Textiles: flax for 7500 yards of linen, 3000 yards wool, ~250 yards of leather (Pig, Deer, Cattle), 20 yards of furs (Beaver, Rabbit, Stoat)
  • Timber: 300 tons
Total Value of Exported Goods: ~1800 GP per year
  • Food 1CP @ 50lbs - 100 GP
  • Metal(iron) 2GP @ lbs - 600 GP
  • Timber 1GP @ ton - 300 GP
  • Flax 1GP @ "42 yards" - 180 GP
  • Wool 1GP @ "25 yards" - 120 GP
  • Leather 1GP @ "1.5 yards" - 375 GP
  • Furs 10GP @ "1.5 yard" - 133 GP
Next post will look at urban wages and will determine prices for common adventuring items based off the information provided here.


  1. How big is a medieval family? Some 5 to 6 people? And how much acres a man can work? What is the upper limit here?

  2. @theorder

    I figured that the average size of a family is 5 to 6 people. Each household on this manor works an average of 30 acres of farmland plus additional acreage of woodlands, pastures and orchard which are apart of the lord's demise. Well-to-do serfs with more access to land (villains) could hire their less fortunate brethren (cotters) to work their land further smoothing out that average.

    The upper limit probably depends on the quality of the draft animals available to pull a plow. (Ye olde plough, if you rather.) An oft repeated rule of thumb is that an acre was measured as the amount of land an ox could plow in one day but I must confess I've never put that to the test. Thus the biggest constraint becomes the window of time available which can be given over to plowing in order to give the crops time to grow. That window seems to be about 30 days.

    Medieval manors were not big on efficiency in a modern capitalistic sense and were more concerned with self-sufficient and the ability to field a knight. There is a diminishing return on investment for the serfs once those goals are met.

  3. On further thought, I'm replacing "family" with "one adult and dependents" where dependents could be a few children and also an invalid adult. Otherwise, there are over 500 actual people running around a manor which is definately too many. The total should be fewer than 200.

  4. When the strip system was used as strip was the distance an ox could pull a plow without resting. As near as I could tell a strip was 220 yards long. I haven't run into any good numbers on the number of strips an ox could plow in a day, which might be fairly variable according to the size and strength of the ox, the health of the ox, the length of the workday, the motivation of the ox driver, etc. You could probably extrapolate a reverse figure by figuring a 30 day planting cycle and divide by the number acres in the manor.

  5. @MLC You are right! That distance is known as a furlong which is the distance an ox could plow without resting. Plowing shorter lengths was impractical because oxen and plows don't corner well. One man and one ox could plow several furlongs in a day with a resulting width of 22 yards, also known a chain. (Guess what was used to measure a chain length?) It so happens that if you multiply a furlong by a chain you get the same result as the area of an acre if you convert to square feet. This was in fact how I did extrapolate some of the 500 lbs of food per acre number.

  6. The ratio between arable and manor population works out fairly well though - 500 people on 3000 acres is 2.5 times more than the higher end average of 200 people on 1200 acres of arable land (which could get lower than that; a dozen tenant families for a german knight is not unheard of, while norman England didn't really keep the 5 hides standard for knights that was true for saxon lesser thanes)