To quote the hoary (but still true) aphorism attributed to the founder of Lever Brothers: "Half of my advertising is wasted, and the trouble is, I don't know which half."

True it still may be - but not for much longer.

After more than a year of infighting, politicking, brink-teetering and corporate footdragging, Project Apollo finally made if off the launch pad last Friday - the day on which it signed the 5,000th household to its consumer panel.

The scheme - a joint venture between Arbitron and ACNielsen - aims to provide single-source market-research that makes a direct correlation between adspend and consumer's purchase of advertised brands.

It links media-exposure information from Arbitron's Portable People Meters to household-purchase data supplied by ACNielsen's HomeScan panel, thereby solving the late Lord Leverhulme's dilemma down to the last penny.

Five thousand homes, say the scheme's proponents, is the 'magic number' necessary to provide clients with bullet-proof data. However, the duo aim to recruit a further 1,250 households to Apollo to ensure the continued generation of statistics from a minimum base of 5,000.

Six advertisers and their ad agencies, led by charter-sponsor Procter & Gamble are now able to receive the Apollo data which analyses their combined annual spend in US measured-media of $6.2 billion (€5.14bn; £3.52bn) .

Other participants in Apollo are Unilever and SC Johnson [WAMN: 06-Jan-06] plus three whose identity remains under the wraps.

Data sourced from AdAge (USA); additional content by WARC staff