Is the rise of mid-cap stocks coming? The SPDR S&P 400 Mid Cap Growth ETF (MDYG) has recently attracted a lot of follow.

This ETF was launched in 2005 and focuses on U.S. mid-cap growth stocks. It currently manages over $4 billion in assets, which is quite impressive.

Mid-cap stocks are quite interesting. Not too big, not too small, seemingly able to balance stability and growth. MDYG primarily invests in companies with a market capitalization between $2 billion and $10 billion. The risk and return seem to be decent.

The fee rate is 0.15%, not expensive. The dividend rate over the past year is 0.72%, which is also acceptable.

Portfolio? Industrial, consumer discretionary, and technology make up the bulk. Industrial is the largest, accounting for about 29%. The top ten holdings include Carlisle, Lennox, and Williams Sonoma. Sounds a bit familiar.

This year has risen by about 16.77%, last year was even more intense, at 25.45%. The beta is 1.08, and the three-year standard deviation is 21.15%. The risk is medium, I guess.

Compared to VOT and IWP, MDYG is in the middle in terms of scale and cost.

Overall, MDYG gives a sense of low cost and transparency. If you're considering a long-term investment, it might be worth a look. However, the specifics still need to be judged by oneself.