Our weekly collection of recent investing articles and personal-finance pieces:

Why do U.S. stocks keep hitting records? (The Wall Street Journal). This WSJ story offers five theories, but does anyone really know? (NOTE: Article is behind paywall. Access it via this Twitter link if you're not a WSJ subscriber.)

Saving for retirement in the most tax-efficient manner possible (USA Today). Don't overlook the impact of taxes on your retirement investments!

What happens to your target-date fund when you hit retirement age (Kiplinger). If you're using a target-date fund in your 401(k), is it a "to" fund or a "through" fund? There's an important difference.

Fidelity Investments fires another salvo in the fee wars (Investment News). The price reductions are for "premium" and "institutional" classes of 14 passive Fidelity funds. "With this action, 100% of Fidelity's stock and bond index mutual funds and sector ETFs will have total net expenses lower than their comparable Vanguard fund," Fidelity boasts in a news release.

Vanguard puts rival firms on notice: Fee wars will only heat up (Bloomberg). "You better be ready to keep lowering price," warns Vanguard's new president and CEO.

(For a broader view of the race-to-the-bottom on fees, read Competition Continues To Cut Investors’ Costs in the August issue of SMI.)

And from the blogosphere...

What will you do when the bear arrives? (Stock Charts). This remarkable bull won't run forever. Do you have a plan?

Time machine and the future returns for stocks (The Simple Path to Wealth). No one knows what the future holds, but a walk down memory lane (through all sorts or turmoils and upheavals) offers a reminder that solid long-term returns don’t require a perfect Golden Age.

Why is there a retirement crisis? (A Wealth of Common Sense). We can’t control the level of future returns, but we can control how much money we set aside.

The impact of early retirement on projected Social Security benefits (Kitces). A "deep dive" on Social Security taxes, earnings, and benefits. Like just about any government-designed system, it's complicated. Really complicated.

Your budget is no place for wishful thinking (The Simple Dollar). Truth bomb: A budget that leaves no room for the unexpected is unrealistic and is likely to fail.

As always, we're interested in your thoughts about any of the topics mentioned above. Tell what you think in the comments section!