Good news round my way and there is a definite trend for teens to leave and it has really increased since about 2010.
In 2013 we "lost" two young girls - daughters of an elder who resigned when they both were announced as no longer unbaptised publishers. The eldest aged about 19 jumped as the elders were closing in on some "serious sin" and the younger aged about 17 said "I don't want this crap" and left about a month later. They are now respectable young women with good jobs and worldly boyfriends in their early twenties.
In 2014 a 16 year old got baptised at the hoopla special convention in August and stopped attending meetings about six months later.
In 2015 a 17 year old decided she didn't want to be a jw anymore and has gone inactive and a 15 year old unbaptised publisher stopped attending meetings about the same time too.
This year (2016) another unbaptised publisher aged 16 hasn't been seen for about two months.
All the above are girls/young women. There is just one uber pioneer teen left and one rather disturbed girl from a difficult background who is not even an unbaptised publisher despite being 14 years old.
It's going "to hell in a handcart" and I believe is down to the factors mentioned by the posters above. Internet/tolerance of gays/apathy/don't believe it.
There are literally no teenage boys in the congregation. There are a few early twenties and then a gap to about ten or below.