I will present new results from the REFINE (Redshift Evolution and Formation in Extragalactic Systems) project, combining in a new reanalysis of the three deepest and large NIR surveys take to date: UDS, Ultra-VISTA and VIDEO for z < 3 systems, and a comparison to CANDELS for z > 3 galaxies. Using consistently measured stellar masses and photometric redshifts for galaxies in these fields, I will show how the major and minor merger rates can be accurately measured for tens of thousands of galaxies. I will discuss the role of both major and minor mergers in the formation of galaxies up to z ~ 6, and compare mass assembly through merging with the star formation rate. I will show that mergers dominate galaxy formation at the highest redshfits, but that star formation is overall a more important process. Comparison to models reveals issues and inconsistencies that show that an empirical approach, such as this, is needed to make conclusions on the assembly process for galaxies. I will also discuss how these results provide unique information about the number of gravitational wave sources LISA will discover based on our observations.