Table 1. Age-Based Stratification of the Gallstone Admissions Showing an Increase in Proportion of Gallstone Disease in Patients Younger Than 20 Years.

Year	(AD)i	(AD-female)i-f	(U20)ii	(GS)iii	(GSF)iii-f	(GSU20)iv	(GSU20:GS)v
1996	2,472,582	1,420,645	177,572	42,911	30,245	877	2.04%
1997	2,436,953	1,398,620	170,473	38,982	27,457	822	2.11%
1998	2,449,696	1,407,077	163,528	37,512	26,396	826	2.20%
1999	2,473,309	1,417,316	165,894	35,833	24,951	779	2.17%
2000	2,549,654	1,460,678	163,898	36,063	25,132	781	2.17%
2001	2,574,758	1,470,400	164,071	35,596	24,375	716	2.01%
2002	2,617,203	1,493,780	160,598	35,691	24,470	792	2.22%
2003	2,696,049	1,536,120	164,333	35,487	24,039	863	2.43%
2004	2,741,495	1,556,981	162,852	35,507	23,880	853	2.40%
2005	2,752,209	1,554,004	161,043	35,041	23,583	813	2.32%
2006	2,771,579	1,563,127	160,628	35,411	23,726	960	2.71%
2007	2,783,498	1,571,481	159,569	35,033	23,194	1008	2.88%
2008	2,809,306	1,581,626	154,745	34,100	22,476	921	2.70%
2009	2,822,537	1,582,478	158,069	34,330	22,448	998	2.91%
2010	2,779,695	1,557,397	148,471	33,612	22,157	997	2.97%

Also refer to study acronyms section. ⁱAD: All discharges irrespective of the age, gender and ICD codes of the discharge diagnoses. ^i-fAD-female: All female discharges irrespective of the age ICD codes of the discharge diagnoses. ⁱⁱU20: All discharges among patients younger than 20 years, irrespective of gender and ICD codes of the discharge diagnoses. ⁱⁱⁱGS: All patients with a discharge diagnosis of gallstone disease. ^iii-fGSF: All female patients with a discharge diagnosis of gallstone disease. ^ivGSU20: All patients younger than 20 years and with a discharge diagnosis of gallstone disease. ^vPercentage of gallstone disease in the young (no. of patients aged < 20 years with gallstone disease/total no. patients with gallstone disease).