Proportion of marijuana bought self-consumed1	Sharing with others2	N (777)	Unadjusted usual gram			Main analysis3 (20% inc/des)
			Mean	Min	Max
All or nearly all	No sharing with others or from other	100	0.96	0.004	10.92	100.0%
	About the same	106	1.68	0.01	55.03	100.0%
	Shared more with others	40	2.65	0.003	14.60	100.0%
	Received more from others	32	1.05	0.06	7.00	120%
	Don’t know or refused	0				100.0%
About three-quarters	No sharing with others or from other	7	0.62	0.05	1.95	75.0%
	About the same	51	0.98	0.01	13.88	100.0%
	Shared more with others	30	1.35	0.06	11.86	95%
	Received more from others	6	0.50	0.15	1.12	105%
	Don’t know or refused	0				100.0%
About half	No sharing with others or from other	15	1.78	0.14	7.32	50.0%
	About the same	107	1.84	0.01	35.17	100.0%
	Shared more with others	38	1.09	0.03	6.46	90%
	Received more from others	5	0.19	0.10	0.67	110%
	Don’t know or refused	1	0.45	0.45	0.45	100.0%
About one-quarter	No sharing with others or from other	13	0.77	0.24	1.59	25.0%
	About the same	44	2.51	0.04	43.08	100.0%
	Shared more with others	19	2.87	0.01	17.44	85%
	Received more from others	3	0.66	0.06	1.00	115%
	Don’t know or refused	5	5.13	0.63	11.50	100.0%
None, all of it was consumed by others	No sharing with others or from other	27	1.98	0.02	27.30	10.0%
	About the same	34	1.17	0.02	11.63	100.0%
	Shared more with others	8	2.68	0.20	14.00	82%
	Received more from others	10	2.42	0.14	5.60	118%
	Don’t know or refused	6	0.71	0.09	1.83	100.0%
Don’t know or refused	No sharing with others or from other	11	0.96	0.18	6.47	100.0%
	About the same	10	0.93	0.13	2.67	100.0%
	Shared more with others	3	0.75	0.33	0.91	100.0%
	Received more from others	9	1.30	0.002	5.60	100.0%
	Don’t know or refused	37	1.01	0.002	8.42	100.0%

¹Survey question: How much of the marijuana or marijuana products that you bought over the past 30 days did you yourself consume?

²Survey question: Thinking about the past month, how does the amount of marijuana that you have shared with others compare with the amounts others have shared with you? Did you share more with others than they shared with you, share less with others than they shared with you, or was it about the same amount?

³In the main analysis, 20% increase or decrease is used to quantify “received more from others” or “shared more with others”, respectively. For example, assuming a person reporting 100 grams of marijuana usual purchase, and reporting “about half” of the purchase was self-consumed, and “shared more with others”. The adjusted quantity accounting for proportion of self-consumption and sharing with others would be 50%+(1−50%)*(1−20%)=90% i.e. 90 grams. In another scenario, assuming still reporting “about half”, but “received more from others”, the quantity would be 50%*(1−50%)*(1+20%)=110%, i.e. 110 grams.

⁴Two types of sensitivity analysis was performed, using 10% or 30% increase/decrease to quantify “received more from others”/“shared more with others” separately.