According to the census, women accounted for 30.9% of those in C-suite roles, up from 30.3% last year – though this number is still some way behind the previous year’s figure of 33.1%.
Below the C-suite, however, female representation fell - 38.2% of departmental heads were women, down from 41.8% a year earlier. Among other senior staff, men made up 53.5%, up from 51%.
People from BAME backgrounds made up 12.9% of the total employed base of member agencies, up from 12.0% last year but still less than 2015’s figure of 13.1%, the highest figure recorded.
In C-suite roles, BAME representation fell, from 5.2% to 4.7%. But it was up at all other levels, with heads of department up from 7.4% to 8.3%.
Paul Bainsfair, director general of the IPA, said: "As our president Sarah Golding rightly said on the release of the IPA Gender & BAME survey in January, we are moving in the right direction in a number of areas, but there is still much we can do in order to accelerate this growth.
"We will continue to watch and support our agencies’ diversity initiatives and hope to see an improvement in these figures over the next few years."
Across the 232 member agencies that took part in the census between July and December last year, there was a marginal increase in total employee numbers, from 25,234 to 25,290.
Broken down by agency type, the census reflects the continued growth of media agencies, which made up 40.6% of the total employee numbers, up from 37% last year and 33% in 2013. The total number of staff in member media agencies, 10,259, is up 44% in five years.
In creative, and other non-media agencies meanwhile, the total number of employees fell 4.9% to 15,031.
Staff turnover across the industry, meanwhile, increased 2.5 percentage points to 31.9%, after it fell 2.7 points last year. For the second year in a row, churn was more than three points higher in creative agencies (33.4%) than media agencies (30.2%).
While the proportion of part-time employees has remained static at 6.1% (1,545 people), there was a sharp drop in the number of first-year trainees and apprentices in member agencies. These fell 20.3% to 860.
Commeting on the data, Cilla Snowball, group chairman and group chief executive of Abbott Mead Vickers BBDO, said: "The new Census data clearly identifies the actions we need to take at company and industry level.
"1.Keep hiring trainees and apprentices, because without a strong youth squad we won't build a sustainable talent pipeline. 2. Drive diversity faster. We need more female leaders and better BAME representation in the industry. Marginal gains just aren't sufficient when the base is so low. 3. Make retention a priority. 32% churn is way too high."