FAQ: how do we calculate blog traffic

[UPDATE--31/12/2008:
Effective for December 2008 survey:

Alexa traffic international rank estimates:
- conversion rates to average unique daily visits:
(Alexa is used to estimate traffic to a blog.)

Alexa international rank = average daily unique visits.

100,000+ = c.1000
200,000 = c.700
250,000 = c.600
300,000 = c.500
350,000 = c.400
400,000 = c.350
450,000 = c.300
500,000 = c.250
600,000 = c.200
700,000 = c.150
800,000 = c.130
900,000 = c.110
950,000 = c.100
1,000,000 = c.90
1,200,000 = c.80
1,300,000 = c.70
1,500,000 = c.60
2,000,000 = c.55
2,500,000 = c.50
3,000,000 = c.45
3,500,000 = c.40
4,000,000 = c.35
5,000,000 = c.30
6,000,000 = c.25
7,000,000 = c.20
8,000,000 = c.15
10,000,000+ = c.10
no data/no rank = c.5

Note that verified traffic stats that have lapsed have been used to estimate the current month's traffic and that for December only, 20% reductions were made in line with the general decline of traffic observed for the blogs disclosing their traffic stats for the December survey period.

Please also note that blogs with no nz Alexa ranking will be rounded down.
--UPDATE ENDS]

Click on image to enlarge.

We use Alexa rankings. 24 of the 174 on our current list use their own publicly viewable meters which allows us to compare how Alexa figures match up with that verifiable data. As we can see from the list below if there is no Alexa rank then the traffic (average daily unique visits) must be presumed to be no more than 50. If there is no nz Alexa rank then it must be presumed to be no more than 100. On the other hand we have Alexa rankings for blogs with traffic of 15 and 25, however this is the exception. Alexa yields approximate traffic and we use it accordingly - until a better method is brought to our attention.

nz233 * 144,589 : c.950 (sitemeter)
nz3,980 * 973,090 : c.650 (sitemeter)
nz2,607 * 951,041 : c. 300 (extremetracking)
nz2,217 * 1,233,404 : c.200 (stats)
nz14,660 * 3,595,101 : c.130 (sitemeter)
nzn/a * 3,412,947 : c.100 (sitemeter)
nzn/a * 7,570,589 : c.85 (extremetracking)
nz8,873 * 1,546,587 : c.80 (sitemeter)
nzn/a * 4,014,091 : c.60 (extremetracking)
nzn/a * 11,323,537 : c.60 (sitemeter)
nz10,452 * 1,292,359 : c.60 (sitemeter)
nzn/a * n/a : c.50 (sitemeter)
nz12,998 * 2,554,252 : c.45 (sitemeter)
nzn/a * n/a : c.40 (sitemeter)
nzn/a * n/a : c.30 (sitemeter)
nzn/a * n/a : c.30 (sitemeter)
nzn/a * 7,719,798 : c.25 (sitemeter)
nzn/a * n/a : c.25 (sitemeter)
nzn/a * n/a : c.25 (sitemeter)
nzn/a * n/a : c.15 (sitemeter)
nzn/a * 2,964,537 : c.15 (sitemeter)
nzn/a * n/a : c.10 (sitemeter)
nzn/a * n/a : c.10 (sitemeter)
nzn/a * n/a : c.10 (sitemeter)

----------UPDATE 27/06/2008-------------

Data: 02/2008 | 06/2008

nz233 * 144,589 : c.950 | nz181 * 132,737 : c.1360
nz3,980 * 973,090 : c.650 | nz4,350 * 887,177 : c.640
nz2,607 * 951,041 : c. 300 | nz2,503 * 775,080 : c.450
nz2,217 * 1,233,404 : c.200 | nz705 * 377,530 : c.550
nz14,660 * 3,595,101 : c.130 | nz? * 4,840,636 : c.90
nzn/a * 3,412,947 : c.100 | nz11,565 * 2,417,252 : c.95
nz? * 7,570,589 : c.85 | nz? * 5,384,784 : c.110
nz8,873 * 1,546,587 : c.80 | nz10,889 * 1,893,397 : c.95
nz? * 4,014,091 : c.60 | nz? * 7,017,841 : c.15
nz? * 11,323,537 : c.60 | nz? * 6,725,162 : c.45
nz10,452 * 1,292,359 : c.60 | nz? * 21,884,975 : c.5
nz? * ? : c.50 | nz28,397 * 3,365,101 : c.50
nz12,998 * 2,554,252 : c.45 | nz32,278 * 3,627,929 : c.20
nz? * ? : c.40 | nz? * 5,463,036 : c.40
nz? * ? : c.30 | nz? * 7,474,254 : c.40
nz? * ? : c.30 | nz? * 9,480,519 : c.25
nzn/a * 7,719,798 : c.25 | nz? * 8,614,821 : c.40
nz? * ? : c.25 | nz31,619 * 8,490,833 : c.15
nz? * ? : c.25 | nz12,782 * 5,440,230 : c.25
nz? * ? : c.15 | nz? * 8,747,460 : c.10
nz? * 2,964,537 : c.15 | nz? * 9,130,735 : c.5
nz? * ? : c.10 | nz? * ? : c.10
nz? * ? : c.10 | nz? * 15,515,390 : c.1
nz? * ? : c.10 | nz? * 11,942,635 : c.10

06/2008:
by nz Alexa rank:
nz181 * 132,737 : c.1360
nz705 * 377,530 : c.550
nz2,503 * 775,080 : c.450
nz4,350 * 887,177 : c.640
nz10,889 * 1,893,397 : c.95
nz11,565 * 2,417,252 : c.95
nz12,782 * 5,440,230 : c.25
nz28,397 * 3,365,101 : c.50
nz32,278 * 3,627,929 : c.20
nz31,619 * 8,490,833 : c.15
remainder by international Alexa rank:
nz? * 4,840,636 : c.90
nz? * 5,384,784 : c.110
nz? * 5,463,036 : c.40
nz? * 6,725,162 : c.45
nz? * 7,017,841 : c.15
nz? * 7,474,254 : c.40
nz? * 8,614,821 : c.40
nz? * 8,747,460 : c.10
nz? * 9,130,735 : c.5
nz? * 9,480,519 : c.25
nz? * 11,942,635 : c.10
nz? * 15,515,390 : c.1
nz? * 21,884,975 : c.5
nz? * ? : c.10