Adjusted for exceptional items and a positive foreign currency translation effect, the operational performance of the SHV Groups showed mixed results compared to 2018. The performance of SHV Energy improved; higher volumes and margins were realised despite warmer weather in Europe. Nutreco performed in line with last year, with like-for-like volume growth in both Skretting and Trouw Nutrition, mainly due to a strong demand and higher margins in shrimp feed and the growth in Asia and Africa. Makro performed slightly below last year, impacted by a challenging market environment in Brazil and hyperinflation in Argentina and Venezuela. The operational performance of Mammoet decreased compared to 2018 under challenging market conditions and strong competition. ERIKS performed below last year driven by lower sales which was not fully compensated by strict cost measures.
In 2019, the effective tax rate decreased from 24.4% to 18.2% amongst others due to recognised deferred tax assets in various Groups, tax exempted book gain on the divestment of the 51% share in Dyas as part of the merger with Oranje Nassau Energie and higher tax exempted results at NPM Capital compared to last year.
The operational cash flow of € 927 million was driven by SHV Energy, Nutreco and NPM Capital. The investment cash flow amounted to € 619 million (2018: € 1,089 million). In 2019 proceeds received from divestments amounted to € 623 million, comprising of the capital gains from private equity investments and the divestment of the 51% share in Dyas. Working capital increased by € 88 million.
A total of € 713 million was invested in operational fixed assets, mainly in gas cylinders and tanks by SHV Energy, heavy lifting and transport equipment by Mammoet and production facilities by Nutreco. NPM Capital invested in Ophen, a fast growing fin-tech company, Zorgwerk, a digital flex staffing company in the healthcare segment, Rooftop Energy, specialised in (rooftop) solar energy, and increased their investments in both Picnic, an online supermarket with free home delivery, and Suitsupply, a globally active company in formal wear. In addition, NPM Capital made several smaller investments in other existing participations. The shareholding in for example Iddink, a seller and rental of schoolbooks, and Outdoor Life Group, a specialist in the production and distribution of garden timber and garden houses, were divested.