Table 2.

Mean age of patients in the group of 50–65 years-old along the period of study. Std. Dev.: standard deviation. Obs: observations.

Year	Mean (age)	Std. Dev.	Obs.
1998	58.19	12.59	118
1999	58.98	12.60	119
2000	56.54	13.20	128
2001	59.84	12.18	129
2002	57.10	12.53	143
2003	57.01	11.97	270
2004	56.12	11.95	243
2005	57.35	13.07	240
2006	57.68	12.48	274
2007	57.43	12.03	283
2008	58.33	12.04	377
2009	58.90	12.15	376
2010	57.17	11.82	367
2011	58.69	12.28	315
Total	57.80	12.27	3382