TTEK vs ACM vs EXPO vs PRIM vs WLDN

For growth investors, Willdan Group, Inc.

(WLDN) is the stronger pick with 20. 5% revenue growth year-over-year, versus 0. 2% for Aecom (ACM). Aecom (ACM) offers the better valuation at 19. 4x trailing P/E (13. 8x forward), making it the more compelling value choice. Analysts rate Aecom (ACM) a "Buy" — based on 25 analyst ratings — the highest consensus in this comparison. The "better buy" depends entirely on your goals: growth investors should weight revenue trajectory, value investors should weight P/E and PEG, and income investors should weight dividend yield and streak.

On trailing P/E, Aecom (ACM) is the cheapest at 19.

4x versus Tetra Tech, Inc. at 33. 0x. On forward P/E, Aecom is actually cheaper at 13. 8x. The PEG ratio (P/E divided by earnings growth rate) is the most growth-adjusted single valuation metric: Primoris Services Corporation wins at 0. 98x versus Exponent, Inc. 's 5. 18x — a PEG below 1. 0 traditionally signals the market is underpricing earnings growth.

Over the past 5 years, Primoris Services Corporation (PRIM) delivered a total return of +234.

4%, compared to -28. 5% for Exponent, Inc. (EXPO). Over 10 years, the gap is even starker: WLDN returned +581. 3% versus ACM's +172. 3%. Past returns do not guarantee future results, and the stock with the higher historical return may already have its best growth priced in.

By beta (market sensitivity over 5 years), Tetra Tech, Inc.

(TTEK) is the lower-risk stock at 0. 53β versus Willdan Group, Inc. 's 1. 96β — meaning WLDN is approximately 266% more volatile than TTEK relative to the S&P 500. On balance sheet safety, Exponent, Inc. (EXPO) carries a lower debt/equity ratio of 21% versus 125% for Aecom — giving it more financial flexibility in a downturn.

By revenue growth (latest reported year), Willdan Group, Inc.

(WLDN) is pulling ahead at 20. 5% versus 0. 2% for Aecom (ACM). On earnings-per-share growth, the picture is similar: Willdan Group, Inc. grew EPS 120. 9% year-over-year, compared to -24. 4% for Tetra Tech, Inc.. Over a 3-year CAGR, TTEK leads at 24. 3% annualised revenue growth. Higher growth typically commands a higher valuation multiple — check whether the premium P/E or P/S is justified by the growth rate using the PEG ratio.

Exponent, Inc.

(EXPO) is the more profitable company, earning 18. 2% net margin versus 3. 5% for Aecom — meaning it keeps 18. 2% of every revenue dollar as bottom-line profit. Operating margin tells a similar story: EXPO leads at 20. 6% versus 5. 5% for PRIM. At the gross margin level — before operating expenses — WLDN leads at 37. 5%, reflecting greater pricing power or product mix advantage. Stronger margins indicate durable pricing power, lower cost of revenue, or higher mix of software/services. They are one of the clearest signs of business quality.

The PEG ratio (forward P/E divided by expected earnings growth rate) is the most precise measure of undervaluation relative to growth potential.

By this metric, Primoris Services Corporation (PRIM) is the more undervalued stock at a PEG of 0. 98x versus Exponent, Inc. 's 5. 18x. A PEG below 1. 0 is traditionally considered the threshold for growth-adjusted undervaluation. On forward earnings alone, Aecom (ACM) trades at 13. 8x forward P/E versus 30. 9x for Exponent, Inc. — 17. 1x cheaper on a one-year earnings basis. Analyst consensus price targets imply the most upside for WLDN: 57. 8% to $117. 50.

In this comparison, EXPO (1.

9% yield), ACM (1. 2% yield), TTEK (0. 8% yield), PRIM (0. 3% yield) pay a dividend. WLDN does not pay a meaningful dividend and should not be held primarily for income.

For long-horizon retirement investors, Tetra Tech, Inc.

(TTEK) is the stronger choice — it scores higher on the combination of lower volatility, dividend reliability, and long-term compounding (low volatility (β 0. 53), 0. 8% yield, +450. 1% 10Y return). Primoris Services Corporation (PRIM) carries a higher beta of 1. 83 — meaning larger drawdowns in market downturns, which matters significantly when you cannot wait years for a recovery. Both have compounded well over 10 years (TTEK: +450. 1%, PRIM: +402. 0%), confirming both are viable long-term holds — but the lower-volatility option typically results in less emotional selling during corrections. Retirement portfolios generally favour predictability over maximum returns. Consult a financial advisor before making allocation decisions.

Both stocks operate in the Industrials sector, making this a peer-level intra-sector comparison — the same macro tailwinds and headwinds will affect both.

In terms of investment character: TTEK is a small-cap quality compounder stock; ACM is a mid-cap quality compounder stock; EXPO is a small-cap quality compounder stock; PRIM is a small-cap high-growth stock; WLDN is a small-cap high-growth stock. TTEK, ACM, EXPO pay a dividend while PRIM, WLDN do not, making them suitable for different income and tax situations. These fundamental differences mean investors should not choose between them on a single metric — the "better stock" depends entirely on which of these characteristics aligns with your investment strategy.