
A case study of a relative strength stock screener run across ~5,000 equities—clarifying what RS scores really imply, how design choices (lookbacks, volatility, sector neutrality) shape signals, and how benchmarks, backtest snapshots, and real-world costs/capacity inform a go/no-go decision.
A case study of a relative strength stock screener run across ~5,000 equities—clarifying what RS scores really imply, how design choices (lookbacks, volatility, sector neutrality) shape signals, and how benchmarks, backtest snapshots, and real-world costs/capacity inform a go/no-go decision.

If your RS screener “works,” why does it still feel unreliable once you try to trade it? Most rankings look impressive in isolation—until you account for universe quirks, volatility, sector waves, and the very real drag of turnover.
This case study walks through RS results across 5,000 stocks end-to-end: what the scores actually measure, the design decisions that changed outcomes, the baselines that kept the test honest, and the implementation lessons that determined whether the edge was tradable.
Relative strength (RS) screener “results” are the behavior of a ranked list, not a single stock pick. You’re reading an output like “top 1% by 6‑month return, rebalanced weekly,” then asking if that basket beats a benchmark.
Across a 5,000‑stock universe, the same RS rule can look brilliant in momentum regimes and ordinary in mean‑reversion regimes. That regime dependence is the line that gets crossed when people treat RS as a universal truth.
Assumptions matter because RS is a ranking game. Change who’s eligible, and you change the race.
A workable 5,000‑stock universe usually looks like:
If your “5,000 stocks” quietly excludes the losers, your hit rate is fiction.
Your screener output is only as stable as its inputs. RS can mean raw returns, risk‑adjusted returns, or ranks that ignore sector waves.
Small input changes can flip turnover and costs, which can flip the whole edge.
You need at least three benchmarks, or you can’t tell skill from beta. RS baskets often look great versus SPY, then look average versus an equal‑weight universe.
Use comparisons like:
Track performance and risk with CAGR, Sharpe, max drawdown, and hit rate, plus turnover and estimated costs. If your “wins” vanish after costs and regime shifts, the screener is just a momentum weather vane.
Your results change fast when you tweak a few “small” parameters. Across 5,000 stocks, those choices also change your trading burden, like slippage and fill quality.
Different lookbacks pick different leaders, and they trade at different speeds.
| Setting | What it captures | Skip-month? | Turnover |
|---|---|---|---|
| 3-month | Fast trend bursts | Optional | High |
| 6-month | Mid-cycle strength | Often | Medium |
| 12-month | Slow regime winners | Often | Low |
| 12-1 momentum | Avoids mean reversion | Yes | Medium |
If your backtest “wins” on 3-month, check if costs ate the edge.
Momentum is easy to rank and hard to hold through stress.
The goal is survivability first; “pretty” CAGR comes second.
Sector-neutral ranking reduces the risk you’re just buying one hot industry. It also changes what “leadership” means when a real momentum regime arrives.
If your mandate cares about benchmark-like sector exposure, neutral ranks help control tracking error. If you’re hunting true leadership, neutrality can cut the winners at the knees.
That’s the line between risk control and intentional concentration.
You need a baseline before you trust any relative strength stock screener across 5,000 names. Otherwise you’re just impressed by a chart that says “up and to the right.”
Use the same fee model, rebalance schedule, and tradable universe for every line below. Different assumptions create fake edges.
| Baseline | What it represents | Fees + slippage | Rebalance cadence |
|---|---|---|---|
| Buy-and-hold S&P 500 | Plain beta exposure | Same as strategy | Monthly |
| Equal-weight universe | Diversification effect | Same as strategy | Monthly |
| Top N by 12m momentum | Simple momentum proxy | Same as strategy | Monthly |
| Sector-relative top N | “Strength” with sectors | Same as strategy | Monthly |
| Random N (seeded) | Luck benchmark | Same as strategy | Monthly |
If you can’t beat “top N momentum” after costs, you don’t have a screener. You have a story.

You want a fast reality check on what a relative strength (RS) screener typically delivers across ~5,000 liquid U.S. stocks. These ranges reflect common monthly rebalances, long-only portfolios, and costs you’ll actually pay.
| Portfolio / Setting | Annualized return (range) | Max drawdown (range) | Realistic costs (annual) | |—|—|—| | Top 10 RS, equal-weight | 14–24% | -20% to -45% | 0.6–1.6% | | Top 20 RS, equal-weight | 12–20% | -18% to -40% | 0.5–1.3% | | Top 50 RS, equal-weight | 10–17% | -15% to -35% | 0.4–1.0% | | Top decile RS, cap-weight | 9–15% | -14% to -30% | 0.2–0.7% | | RS + trend filter (MA) | 11–18% | -10% to -25% | 0.4–1.1% |
If your backtest sits outside these bands, assume a bug or a hidden constraint.
Backtests look clean because they ignore the messy part. Your real edge is your edge after spreads, slippage, fees, and taxes.
A 40% gross CAGR can die from 150 bps of friction. The spreadsheet still says “works.”
You need a cost model before you trust any “relative strength” curve. Otherwise, you are grading the strategy on a closed-book test.
Calibrate these to your universe, or your alpha is just a rounding error.
Turnover is just trading volume in disguise. Convert it to bps, then ask what alpha must beat it.
If your required alpha is above what the factor ever delivered live, size down or slow down.
Capacity is where “5,000 stocks” quietly becomes “the top 300 that actually trade.” Liquidity limits, position sizing, and rebalance urgency decide what fills you get.
A common heuristic is 1%–5% of ADV per name per day, with tighter limits in small caps. Concentration is the second trap. The highest relative-strength names often cluster in smaller, hotter stocks, so a top-N portfolio can drift into a micro-cap fund without you noticing.
As you increase N, you usually improve fill quality and reduce impact, but you also dilute the signal. That trade-off is the real knob for scalability.
I ran a weekly rebalance across ~5,000 US stocks to see what survived real constraints, not backtest hygiene. The live-like version bought the top 50 or top 100 relative strength names, equal-weighted, capped at 10% per position, and filtered for liquidity so fills were plausible.
Rules were simple: Monday rebalance, trade within the first 30 minutes, and assume frictions. I modeled 10–25 bps per side in fees and slippage, plus a one-day signal delay to mimic “you only know it after the close.”
Most RS edges aren’t killed by math. They’re killed by your calendar and your fills.
You can’t manage what you don’t measure, and RS systems drift fast month to month. Track these every month, not just at year-end.
If RS decay steepens, your “weekly” system is secretly a “daily” one.

The clean equity curve broke in the same places every time: gaps, earnings, and crowding. With a one-day delay, about 15–25% of names were no longer in the top bucket by the time you could trade.
Earnings weeks did the real damage. Overnight gaps pushed single-name P&L swings 2–4× normal days, and the 10% max position cap still didn’t save you from clustered risk.
Top-50 looked sharper, then costlier: turnover ran ~20–40% higher than top-100, and net returns fell by roughly 0.5–1.5% per year after modeled costs. Small parameter tweaks mattered too; changing the lookback by a few weeks shifted sector exposure enough to move max drawdown by several percentage points.
Your edge isn’t “RS works.” Your edge is the version that still works when the tape fights back.
Relative strength (RS) screeners work until the market regime changes. Your edge often dies quietly, then shows up as a sudden cluster of “unlucky” losses. Treat disappointment as a diagnostic problem, not a vibes problem.
Momentum crashes and bear rallies flip the leaderboard fast. Macro reversals do it too, because RS is usually a hidden bet on liquidity and rates.
Watch for measurable “risk-off” thresholds that correlate with RS drawdowns:
A common tell is a bear rally where low-quality rebounds lead for 1–3 weeks, while your leaders lag. When those signals cluster, reduce leverage and shorten holding periods before your screener “finds” pain.
You can make RS look brilliant by tuning it to one tape. Robust RS survives ugly periods with only a dent, not a personality change.
If small parameter nudges flip results, you built a curve-fit, not a screener.
Most RS “alpha” bugs come from data, not math. Bad inputs quietly inflate winners and erase losers.
If your backtest never holds a stock that later dies, your dataset already lied to you.
A relative strength (RS) screen across 5,000 stocks is only investable if it survives real-world friction. Think “looks good on a chart” versus “still works after costs, slippage, and regime shifts.” Your job is to decide if this is a strategy, or just a sorting tool.
You need explicit thresholds before you risk money, because ambiguity turns into rationalization. Set the bar upfront, then let the data reject you.
| Criterion | Go threshold | No-go trigger | Notes |
|---|---|---|---|
| Net alpha | ≥ 3% annualized | ≤ 0% | After all costs |
| Sharpe (net) | ≥ 1.0 | < 0.7 | Live-like assumptions |
| Max drawdown | ≤ 20% | > 30% | Same sizing rules |
| Turnover | ≤ 150%/yr | > 250%/yr | Tax + slippage load |
| Capacity | ≥ $10–50M | <$5M | Depends on liquidity |
| Robustness | Pass 4 checks | Fails 2+ | See below |
Robustness checks to require:
If you can’t clear these bars, you don’t have a strategy yet. You have a hypothesis.
RS screening works best when you can follow rules during ugly periods, not just backtests. It favors investors who treat it like a process, not a prediction.
Systematic traders benefit most, because they can enforce rebalancing, sizing, and cost models. Long-only allocators can use RS as an overlay, but should demand low turnover and sector controls. DIY quants can run it in small accounts, but taxable accounts get crushed by short-term gains and churn.
If your account can’t tolerate turnover, your “edge” may be a tax bill.
Backtests don’t pay commissions. You need a live-like proving ground before scaling.
The first goal isn’t profits. It’s proving the backtest survives contact with your broker.
Your screener results only matter if they translate into a repeatable daily process that respects regime shifts, capacity limits, and common failure modes.
Open Swing Trading delivers daily RS rankings, breadth, and sector/theme rotation context across ~5,000 stocks so you can surface breakout leaders faster—get 7-day free access with no credit card.