Burnup derived from different Nd isotopes (¹⁴⁸Nd, ¹⁵⁰Nd, ¹⁴³Nd+¹⁴⁴Nd, and ¹⁴⁵Nd+¹⁴⁶Nd) according to the approach proposed by Boden et al. [17] (left column) and in this work (right column). The same set of data is expressed as a function of burnup (top row), Pu content (second row) and reactor type (third row). The ratio of average burnup to reported burnup is presented in the bottom row. Here, only data for which the burnup was assessed by cross check analyses are withheld.