Soxos, there is a lot of turmoil in the ad world right now and you have not indicated your traffic. Unless you have several thousand daily page views, such turbulence is possible.

Hi ecmedia,
No this site has week day daily 500-600 page impressions per day - its only a small site I wanted to try adsense on.

Do you believe the huge drop in eCMP to be normal turbulence rather than anything to do with making it a targetable ad placement? It just seems really strange to both occur on the same day.

If I was to try a larger site, do you think I should remove the small site entirely or keep it running and just add the larger site?

Thanks

Actually I noticed recently when I was trying out some new ad units that they performed better before I made them available for placement by advertisers, I thought it was just coincidence but now I'm wondering... Soxos there's only one way to find out uncheck the box or create a new ad and test it out.

You're calling 5-pound eCPM "dreadful"? Are we living in the same world? I would kill for that kind of rates!

I am struggling with sub-$1 eCPM and my traffic is the highest quality there is, mostly US, no-kids $100K+ earners (according to Quantcast).

Hi loudspeaker, I apologise, as I have only experimented with this one site, I consider £5eCMP poor NOW, as for the first 3 months the adsense was on it was often above £100 eCMP. Perhaps I am just expecting too much? It is not really the numbers that bother me, but the fact there was a sharp, instant almost drop - until I figure out why this happened I feel like I have not learnt anything from the test I did with this first site :(

Perhaps I am just expecting too much?

I guess so.

What traffic levels are you talking about? You mention a "small" old site. How small is it, really? How many unique visitors do you see per day/month? How many pageviews (ballpark figure)?

One explanation for your problem could be that the numbers are fairly small, but the earnings per click are very high. In order to get an eCPM of $100 with 5% click-through, each click averages $2.00

For example:

100 pageviews
x 5% Click-Through
= 5 Clicks

x $2.00 Earnings per click
= $10.00 Revenue

eCPM = $10.00 revenue/100 pageviews x 1,000 = $100.00

Now, an average EPC of $2.00 is unlikely to be sustainable as traffic grows. Add in the economical crisis, and it's easy to see why your eCPM has dropped off. And yes, I am with loudspeaker being jealous of your 5 pound eCPM. ;-)

Yes Zett, your assumptions are quite accurate, although more like:
200 page views per day x 5%

Revenue per day was around $10 - $15 dollars, so you pretty spot on really. Now it is more like $5, as although eCPM is way down page impressions are up to about 400/day (according to adense)

My stats show pageviews at aroun 800/day now (when I starts using adsense about 5 months ago it was only about 500/day)

So my conclusion should be
1) the first few months where just a combination of luck and good timing.
2) ticking the "show as ad placement box" was just a terrible coincidence and although it occured the same day as the nose dive i should try and block it out as a reason.
3) current results / clicks are quite typical.

Thank you all for shed some light on this.

Now what do you suggest i do, as i think i just need to try it on one of my main sites - should i remove this small one or just have 2 in one account. Someone once told me you get lower eCPM if you have different sites in the same account as they can drag each other down.

Complicated stuff this adsense, im used to affliate schemes - but hey you have to try all things!

soxos,
It could be that advertisers have been charged for a click that they feel was to high and it didnt give them a return for their money. They may have blocked your site and if several good advertisers block your site, your revenue goes down. On top of that the economic crisis and the overall advertising industry is currently not doing well. Just my 2 1/2 cents.