Unfortunately they have been in great decline in recent years, much of it due to the effects of global climate change. (sciencedaily.com)
Without that there will be a greater and greater decline in sales. (bigpicture.typepad.com)
However, both life and relationship satisfaction decrease over time, with greater declines seen in relationship satisfaction relative to life satisfaction (likely because the addition of a child detracts from time romantic partners can spend together). (scienceofrelationships.com)