Consider the following trading and performance data for four different equity mutual funds:

Fund $W$ Fund $x$ Fund $Y$ Fund $Z$

Assets under Management, Avg. for Past $12$ months $($mil$)$ $$289\mathrm{.}4$ $$653\mathrm{.}7$ $$1,298\mathrm{.}4$ $$5,567\mathrm{.}3$

Security Sales, Past $12$ months $($mil$)$

$$37\mathrm{.}2$$$569\mathrm{.}3$$$1,453\mathrm{.}8$$$437\mathrm{.}1$

Expense Ratio

Pretax Return, $3-$year avg.

Tax$-$adjusted Return, $3-$year avg.

Calculate the portfolio turnover ratio for each fund.

Which two funds are most likely to be actively managed and which two are most likely passive funds? Explain.

Calculate the tax cost ratio for each fund.

Which funds were the most and least tax efficient in the operations? Why?