This way ages are calculated for each of the spot analyses and line scan, which each consist of multiple mass sweeps. For line scan analyses on NIST610 the number of mass sweeps is between 280 -580, depending on dwell times and length of the line scans (Table ). For spot analysis, the number of mass sweeps is either 97 (sessions "GER2B/Wil1A" and "GÄD08") or 151 session "homogeneity".