The advantage of the C-constant is that it is directly associated with the relevant anatomy of the anterior segment and not dependent on the k readings or other factors. Therefore, the C-constant works in short and long eyes and would even work in other species if an IOL is implanted in the capsular bag using similar technique. In a clinical series on more than 1700 eyes, Dr. Olsen assessed the performance of the Olsen formula as compared to standard formulae like Holladay 1 and SRK/T. All measurements were taken with Lenstar and independently of the eye length, the Olsen formula using the concept of the C-constant and paraxial and exact ray-tracing outperformed the standard formulae.