Neighbourhood Pool Watch: 9.10 ASIC choices: Avalon update 3

0. Introduction
Errata: In post 9.9 I made a late night error, incorrectly naming a variable. This lead to Difficulties being applied one retarget early, and thus underestimating earnings. This has been fixed for this post. All previous "ASIC choices" posts are not affected.

Bitcointalk.org forum members MrTeal and schmadz requested a slightly different data presentation, which I think will be more flexible than previous presentations. The changes are:

Daily and cumulative earnings are in BTC
Daily and cumulative earnings do not account for power costs.
Daily and cumulative power costs are shown in two other charts.

If you want to estimate costs, then convert to US$ using whatever rate you think will be appropriate (US$25 to US$30 / BTC are probably safe values) and then use charts three and four to calculate costs. (more details in charts sections).

This removes the necessity of using scenarios, and allows much greater flexibility.

In this post I had written:

Batch 3: 600 units arrive from 17th April to 18th May.
Batch 3: 600 units arrive from 17th May to 18th June.

This was a typo and should have been:

Batch 3: 600 units arrive from 17th April to 18th May.
Batch 4: 600 units arrive from 17th May to 18th June.

There are only 600 units in batch 3.

1. Assumptions
These have been changed to reflect the current guesses about ASIC manufacture. Avalon shipping dates have been adjusted, BFL hashes shipped per day has been increased and ASICMiner has only 10Thps left to add to the network hashrate. I have also assumed a "batch 4", even though there has been no news about one, so that earnings could be extrapolated a month further.

Only 67 Ghps Avalon models are being considered.
Arrivals are constant. Rather than modelling arrival times, I'm assuming a constant rate of hashes per second added to the network for each of the batches.
Batch 1: 300 units arrive from 18th February to 17th March.
Batch 2: 600 units arrive from 17th March to 18th April.
Batch 3: 600 units arrive from 17th April to 18th May.
Batch 4: 600 units arrive from 17th May to 18th June (please note there is no conformed batch 4, this assumption is for modelling earnings to July for the earlier batches).
BFL delivers 2000 Ghps per day (~35 SC Singles per day) from 17th February to 17th June.
ASICMiner delivers 1000 Ghps per day from 17th February to 1st March
Initial difficulty = 3 650 000
Initial network hashrate = 27 000,
I'm still assuming no GPU miners leave so these charts will underestimate earnings for all batches - but batch 1 will be underestimated the most.

2. Charts

The first group of charts show the expected hashrate, difficulty and blocks per day given my assumptions.

The next set of charts show:

Expected cumulative BTC earnings, when starting mining at the start of each month and the middle of each month.
Daily BTC earnings.

The last set of charts shows the cumulative electricity costs and daily electricity costs for miners in 220V and in 110V countries.

3. How to estimate earnings

Decide when you think your Avalon will arrive and the US$ exchange rate, and use the cumulative earnings chart to determine the estimated USD$ earning amount.
On the appropriate (110V or 220V) cumulative electricity costs chart, select the on the x axis of the number of days mining of which you wish estimate the cost, and on the y axis your electricity cost per kWh. The estimated cumulative cost of mining can be read from the colourbar on the side.
Subtract the electricity costs from the US$ earnings.

Example: You hope your Avalon ASIC will arrive on the first of April. The cumulative btc earned by 18th June (the maximum x axis value) is ~ 80 BTC. You're bullish about BTC, and you estimate the exchange rate will be US$30 per BTC at that point, earning you a total of US$2400 in 78 days.

You live in California, so you have 110 V mains and your electricity costs are US$0.35 per kWh. From the upper cumulative electricity chart, you mark the intersection of 78 days (x axis) and US$ 0.35/kWh (y axis) and by matching the colour from the colour bar, estimate a total cost of ~ US$400 (click on the chart for a closer view).

In this case, the amount earned will be US$2000.

If you dont want to use the charts, the cumulative cost will be:

cumulative daily electricity cost = device watts * cost per kWh / 1000 * days * 24

4. Conclusions

I'm much more positive about the ability of the Avalon ASICs to earn, at the very least, a complete ROI. For example, in my locality even if your ASIC arrived May 1st it would still earn (after electricity costs and assuming a US$28/BTC exchange rate) about $1200 by mid June.

My assumptions are an unknown quantity. The estimates about ASICMiner's start date and hashes added per day were very close, but so far only a third Avalon has been spotted in the wild, and no BFLs were delivered yesterday (my assumed start date) so earnings may be even better.

If BFL ship more than 2Thps per day however, earnings will suffer in proportion to the increase.

Let me know if these charts were easier to follow than the previous charts, and if not how they could be improved. If anyone wants them, I'll post the datasets.

Thanks to MrTeal and the quite generous schmadz for their suggestions.