An aqueous suspension at 60°C is fed to the first effect of a double effect forward feed evaporator with a mass flow rate of 1.25 kg s^-1. The sum of the rates of water evaporated from the first and second effects is 1.0 kg s^-1. Temperatures of the exit streams from the first and the second effects are 100 °C, and 60°C respectively. Consider the specific heat of the aqueous suspension, and the latent heat of phase change for water to be 4 kJ kg^-1K^-1 and 2200 kJ kg^-1 respectively, over this temperature range. The steam economy (in kg per kg) is _______ (round off to 2 decimal places).