Something you have to realize about longterm investing...

Today you buy $100k of a stock fund and you get 1000 shares worth $100. The next day the markey crashes and drops 80% of its value. How many shares do you own now? Well...still 1000, they are just $20 a share now. That only matters if you withdraw the money then. Almost certainly in 10 years those shares will be worth more than $100 a share...and you still have 1000 shares.

Number of shares matters. Value of shares only matters when you cash out. If you are longterm investing what the market is doing right now doesnt really matter.