Year	AOD (440)	Standard deviation	Angstrom₄₄₀_-₈₇₀	Standard deviation	PW (cm)	Standard deviation
1998	0.484	0.295	0.709	0.266	3.822	0.318
1999	0.608	0.406	0.769	0.295	3.487	0.421
2000	1.275	0.560	0.503	0.163	1.81	0.627
2001	0.742	0.582	0.666	0.267	3.286	0.415
2002	0.533	0.376	0.783	0.235	3.035	0.415
2003	0.866	0.550	0.689	0.239	3.569	0.543
2004	0.712	0.333	0.76	0.22	3.187	0.487
2005	0.728	0.416	0.672	0.223	3.588	0.466
2006	0.748	0.523	0.69	0.273	3.493	0.428
2007	0.769	0.518	0.678	0.264	3.332	0.443
2008	0.740	0.516	0.673	0.209	3.125	0.388
2009	0.793	0.458	0.704	0.215	3.326	0.273
2010	0.978	0.387	0.817	0.193	2.347	0.503
2011	0.549	0.329	0.858	0.213	3.043	0.405
2012	0.795	0.589	0.718	0.232	3.468	0.448
2013	0.593	0.318	0.82	0.287	3.417	0.387