1. Ministry of Health and Welfare, 1987 Patient Survey
(
Tokyo
:
Kousei Tokei Kyokai
,
1989
).
Yen has been converted to U.S. dollars at the rate of 135 yen to one dollar, except when purchasing power parity was used
.
2. Kyokai Kousei Tokei
,
Hoken to Nenkin no Dokou
(
Tokyo
:
Kousei Tokei Kyokai
,
1989
),
76
-
77
,
63
.