While earnings rose by 28% in local currency over the five years to the end of 2015, they fell by 3% in the eurozone.
The group said this was the main driver for returns in their respective equity markets over the same period, which increased by 25% on the continent and by 63% in the US.
NNIP said in spite of the long-term recovery potential in the eurozone the group’s house view was still underweight European equities.
Patrick Moonen, principal strategist, multi asset at NNIP, said: “This is related to the political uncertainty in the region for at least the next 11 months and the potential negative impact of the steep 20% depreciation of GBP against the euro on the earnings growth of eurozone companies.”
The group said the gap in earnings growth might be due to the lower nominal growth between the regions, as well as the varying performance of sectors in both markets.
It said comparable profitability in the US was higher for every sector, as was the average net operating margin – 13% in the US versus 9% in the eurozone between 2010 and 2015.
Moonen said: “An interesting point is also the sensitivity of the earnings to changes in the revenue growth.
“The operational leverage of the eurozone market is higher than in the US. This would imply that if nominal economic growth picks up, earnings growth in the eurozone would be higher than in the US.
“We also think that given the slack in the economy and in the labour market, companies in the eurozone have more potential to increase profit margins.”