BMW Group published the June sales figures today. Once again, i3 and i8 sales have been amalgamated. My guesstimate is that roughly 80% of those 2071 vehicles are i3s.
http://www.bmwgroup.com/bmwgroup_prod/e/0_0_www_bmwgroup_com/investor_relations/corporate_news/news/2015/vertriebsmeldung_juli_2015.html
Sales of BMW i vehicles are up more than 65% on the same time last year, totalling 2,071 for the month. In the first half of this year, 12,562 customers took delivery of a BMW i vehicle.
http://www.bmwgroup.com/bmwgroup_prod/e/0_0_www_bmwgroup_com/investor_relations/corporate_news/news/2015/vertriebsmeldung_juli_2015.html