The headline GMI figure, which takes into account marketers' expectations in three key areas – marketing budgets, staffing levels and trading conditions – slipped back 0.3 points on the previous month to 58.0 but was up 1.5 points over the year.
Warc's GMI is a unique indicator of the state of the global marketing industry. Each month, it tracks conditions among marketers within their organisation and region - a reading of 50 indicates no change from the previous month, while a reading of 60 indicates rapid growth.
Marketers' confidence remained highest in the Americas, where the headline GMI recorded 59.3, followed by Europe (57.2) and then Asia Pacific (57.1).
For the component parts of the index, the global figure for marketing budgets remained steady on 55.7, but there were distinct regional variations. There were rises for the Americas, up 2.1 points to 57.8, and Europe, up 1.6 points to 56.7, but Asia Pacific fell 2.6 points to 53.0.
On trading conditions the global index edged up 0.3 points to 61.4, with Europe performing especially well as it recorded a 3.4 point jump to 62.3, returning it to the levels seen earlier this year.
The index for trading conditions in the Americas fell 3.2 points, but at 60.3 this was still a very positive indicator. Asia Pacific was on a similar figure, slipping 0.2 points to 60.2.
The final component of the headline GMI, staffing levels, fell by 1.2 points globally in May to 56.8, but continues to signal improving conditions overall. This measure was down sharply in Europe, as a 5.7 point fall left it on 52.7. The Americas saw a more modest decline, from 60.5 to 59.9, while Asia Pacific increased from 56.3 to 58.1.
Commenting on the figures, Suzy Young, Data and Journals Director at Warc, said: "May data show that the outlook for global marketers remains broadly in line with recent months, with confidence high in all regions. Conditions are now considerably less volatile than this time last year, which is encouraging for both the industry and the global economy."
Data sourced from Warc