Year	PPG (TDS, current US$)
1981	306715.9
1982	1456523.5
1983	2954345.3
1984	5241449.1
1985	4720433.2
1986	4689991.1
1987	7784717.4
1988	7800349.2
1989	6456974.7
1990	5621384.1
1991	7835477.4
1992	10479069.4
1993	6520806.9
1994	9173993
1995	8990449.6
1996	7774308.2
1997	14576032.2
1998	19503039.7
1999	19823670.2
2000	16126554.6
2001	13689727.1
2002	22886487.1
2003	19009809.9
2004	23988572
2005	35633908.8
2006	31480733.4
2007	29202172.2
2008	30504091
2009	31309584.4
2010	32713446.8
2011	35056595.7
2012	33183561.5
2013	37051751.5
2014	42062925.2
2015	41509611.9
2016	43702343.7
2017	50695857.9
2018	55862038.3
2019	60597648
2020	59275736
2021	54463109.7
2022	97037870.9