I’ve been playing Farmville, a social video game by Zynga, over the past week, and I have to say that I’m extremely impressed. It’s a very simple simulation game, with well integrated social aspects to promote virality, a good technology tree, and clever virtual goods integration.
If you’ve played the game (and at this point, approximately 9 million people have), then you are likely already familiar with the primary economics of the game. As a farmer, you have a certain number of plots. It costs money (coins) to plow a plot and plant seeds. Different crops take different amounts of time to grow, and are worth different amounts at harvest. Quite simply, the question is:
Which crops should you plant?
Since I do love an excuse to crack open Excel, I built a simple model that tells you what crops are the “most valuable” to plant. My model was simple:
- Revenue is just the value of the crop at harvest
- Cost is the cost of the seeds + the cost to plow the square
In order to compare crops, I had to normalize the values:
- Normalized all revenue and costs to “one square”
- Normalized all revenue and costs to “one day”, namely 24 hours
Thus a crop like Strawberries, which takes 4 hours to grow, can be theoretically planted 6 times in a single day. Eggplant, which takes 2 days to grow, can be planted 0.5 times in a single day.
This model gives you the following simple table as output, ranked by “coins per square per day”:
|Crop||Profit / Day|
(Note: I still haven’t gotten the revenue and cycle time for the new crops, Red Wheat and Yellow Mellon)
Most of the strategy guides that I’ve found across the web have basically gone just this far.
The problem with this model, however, is pretty obvious:
It assumes that your time has no value!
Listen, Raspberries might be #6 on this list, but you have to actually harvest and replant 12 times per day! (It’s a two-hour crop). That only seems reasonable if you truly value your time at $0. Theoretically, we should give some non-zero value to the time it takes to replant, and see how it affects the rankings.
To do this, I changed the model based on the following assumptions:
- It takes roughly 15 minutes to replant your farm with a crop
- 1500 Farmville coins are worth $1 (which is what Zynga charges to buy coins with PayPal or your credit card).
I then graphed out the ranking of the crops on a spectrum from $0.00 / hour value for your time, all the way to $1.00 / hour.
As you can tell from the range, the bad news is that even the best crop flips to being “negative value” per day at a monetary value of approximately $0.70 / hour.
click the image to see enlarged verson
This graph paints a very different picture. If you rank crops by what hourly wage “zeroes them out” in value, you find that actually, your top three crops should be:
- Broccoli ($0.69 / hour)
- Corn ($0.57 / hour)
- Watermelon ($0.54 / hour)
If you accept the idea that 1500 Farmville coins is worth $1 (which is a bit of a stretch since you can’t convert back to dollars…), then these are the crops that pay you the best “hourly wage” for your time.
There are a few things I’ve left out here:
- Trees / Animals. I haven’t run these numbers for trees or animals, but it would be trivial to do so.
- Working capital. These crops require different amounts of liquid cash in your Farmville account. That capital theoretically has a cost, but I didn’t model it.
- Experience. Some people are playing for experience points, not coins. Ignored here.
- Capital Risk. The different crops have different windows of time to harvest before your revenue goes to zero and your crops wither. This analysis assumes a “perfect farmer”.
If you find this model interesting or useful, would love to see links back here from anyone who pursues any of these different issues.
Of course, that assumes that there is someone else out there twisted enough to spend time analyzing the personal economics of Farmville…
Let’s just say there is a reason Super Berries are, well, super:
|Crop||Profit / Day|
Not surprisingly, the quick cycle-time of the berries dominates this table.
The question is, how do you blend the value of experience and coins? The truth is, the function for valuing experience is probably too complicated to get right.
However, I did find a simplistic proxy. 1 experience point = 15 coins.
Why? Well, it turns out you can just sit there, plow a square for 15 coins, and get 1 experience point. You can then delete the square and do it again. So at least, in theory, you can “buy” an infinite supply of experience points for 15 coins each.
When you include experience at this price, the rank of the crops changes significantly from the original “coins only” version of the most profitable crops:
In many ways, this final table is a more satisfying answer on what to plant, since it gives a fairly balanced view across coins (which are needed to buy seeds, tools, and other items) and experience (which is also needed to raise your level to buy seeds, tools, and other items).
Clearly, this analysis is very sensitive to the value of an experience point. The more value you ascribe to experience, the more the compound table begins to resemble the experience-only version.
As part of my original post, I had run some analysis that suggested that if you value the time that it requires to check on your crops, harvest them, and re-plow & plant, then you might get a different order. I’ve now updated the chart to include the three crops that I didn’t have yesterday.
click to see the enlarged chart graphic
Based on the addition of the new crops, the top five crops in terms of their value in $ US / hour are:
All of the values are still well below $1 / hour.
I re-ran these numbers utilizing the experience points. While they did shift the numbers to the right, they didn’t alter the ranking significantly. This is likely because the cost in time (15 minutes) for each cycle and the high conversion rate (1500 coins / $1 US) means that the time cost of checking dwarfs the incremental value of the experience per cycle.
That’s why you can see that one wacky line, Super Berries, which starts so high it’s off the chart, but crashes down under the weight of 12 cycle refreshes per day.
A couple people specifically wanted to see this analysis taking into account the new Tractor, which speeds plowing by up to 4x (although you need to buy fuel). Since I don’t have a Tractor yet (working on it), I estimated what would happen if a cycle plow/plant took only 5 minutes instead of 15. Here is the updated chart:
click to see the enlarged chart graphic
For those of you playing at home, sorry to disappoint. It turns out that dropping the time it takes does shift the value per hour out almost linearly. You’ll note that in this chart, now the equivalent value for Yellow Mellon is over $2.62 / hour. The order of the most valuable crops, however, does not change, because even five minutes dominates with such a high US $ to Farmville coin exchange rate.
Abhi did make one last point that I agree with completely. The primary value of the game is not the coins you make. (In fact, since you can’t really convert coins back to dollars, they are arguably worthless.) The value is the fun and enjoyment you get from the time spent.
In fact, I could theorize that if you normally bill $50/hour for your time, the delta between your normal rate and the amount you are making with Farmville crops shows just how much you value playing Farmville.
Hope this post was as interesting to folks as the last. I’ve got to go harvest some Super Berries…