Data fields in Salmon_N_means_FW.txt are:
Sample:Unique sample identifier (one per laboratory sample)
Cut: nature of the sample (Whole fish or fillet)
Size: Size of the whole fish prior to sample preparation (small, medium, large)
Country: Country of origin of the sample (Scotland, Norway)
Season: One of four northern hemisphere seasons indicating the time of year (2006-2007) at which samples were taken
Nitrogen, Fat: Nitrogen and fat content, in g/100g (mass percent)
Defat.N: Nitrogen as a proportion of defatted material, defived from nitrogen and fat content.