Why did the proportion of household savings in the USSR decrease during its transition period? This question came out as a multiple-choice in my A-Level Economics exam. The answer choices were: 

A) Rising income inequality
B) Increased availability of consumer goods 
C) Rising medical expenses 

Without actual information, the question is debatable. I am not sure why this we were asked to hypothesise without adequate information.
I couldn't say what was the actual explanation but Increased availability of consumer goods could deliver this result. Say people in the USSR expected that eventually there would be a consumer revolution where their choice of goods would be better. Then utility would look like something like this:
$$ U(c_1, c_2, c_3) = ln(c_1) + \beta \cdot \xi \cdot ln( c_2) + \beta^2 \cdot \xi \cdot ln( c_3)$$

where $c_i$ is the consumption in period $i$, $\beta$ is the discount rate, and $\xi &gt; 1$ indicates how much better consumption is in time 2 than 1. A higher value of $\xi$, meaning a greater improvement in consumption acts like a higher value of $\beta$, meaning lower discounting of future consumption in period $1$. That means that households will (all else equal) save more in period 1. In period 2 there is no expected increase in the quality of consumption, only the standard time discounting differentiates consumption in the present and future, and so the savings rate (relative to period 1) falls, just as it would if $\beta$ fell.