SFE as a function of redshift. A general trend of increasing SFE with redshift is seen. SFE as a function of redshift. A general trend of increasing SFE with redshift is seen. This trend is more prominent in the starburst population (above the MS) identified by the blue border squares around the circles in the plot. Top-panel: dependence of the results on the age of the starburst (in the colour-bar). There is a clear dependence between the efficiency of star formation with the age of the starbursts: the later the starburst in the age of the galaxy the more efficient the star formation. Bottom-panel: same SFE-redshift plot with the dependence on the fraction of the star-formation burst (in the colour-bar), the more significant burst, the more efficient the star formation.