Tdirectory  # entries just after Ttree::Write  cycle  # entries after reopen  difference
----------  ---------------------------------  -----  ----------------------  ----------
 year_1993                             72,019      2                  72,019
 year_1993                                         1                  67,509       4,510
 year_1994                             93,851      2                  93,851
 year_1994                                         1                  59,274      34,577
 year_1995                             46,412      1                  46,412
 year_1996                             71,750      3                  71,750
 year_1996                                         2                  62,036       9,714
 year_1997                            144,385      6                 144,385
 year_1997                                         5                 141,107       3,278
 year_1998                            309,882     11                 309,882
 year_1998                                        10                 284,037      25,845