The operators of one of the most controversial road schemes in the country generated more than €370,000 per week in operating profits from the route last year, despite suffering a significant slump in revenue overall.
The M3 motorway generated €19.25m in operating profits for Eurolink Motorway Operation (M3) Ltd in 2013, down from €30.2m the previous year, newly filed company records show.
In total, the firm recorded €29.5m or €80,843 per day in revenues in 2013, a major drop on the €39.88m recorded in revenues in 2012.
Daily traffic volumes increased by 2.35pc on the route last year to 23,000 vehicles - the firm's revenues are made up of road tolls and operational payments from the National Roads Authority (NRA).
The road tolls are generated by a €1.40 charge to motorists at each of the two toll plazas on the route.
The payments from the NRA include traffic guarantee payments that are paid if sufficient volumes of motorists don't use the tolled route.
The guarantee was put in place due to the high cost of the route and due to it being a challenging project to deliver.
A recent Department of Transport memo confirmed that just under €3m was paid in traffic guarantee payments to the M3 firm last year.
The 51km motorway that runs from Clonee to north of Kells was built at a cost of almost €1bn.
The scheme was the largest infrastructure scheme delivered through a Public Private Partnership (PPP) at the time.
The M3's construction caused controversy and was targeted by protesters as it runs near the ancient Hill of Tara archaeological site.
Eurolink Motorway Operation (M3) Ltd is jointly owned by Irish firm Siac Construction and a subsidiary of the Spanish company Ferrovial.
The company last year approved a dividend of €2m to the firm's shareholders and this followed a dividend pay-out of €7m in 2012.
The figures show that the firm's pre-tax profits more than halved from €17.6m to €8.27m.
The significant difference between operating and pre-tax profits arose from the firm paying €11.1m in bank interest payments to finance the loans used to construct the route.