Stratsemble
Preparation · Stage 2 of 5 — Test
TMUS · T-Mobile USStocks

Does the Parabolic SAR strategy beat buy & hold on T-Mobile US? (TMUS · backtested honestly)

Wilder's 'stop and reverse' dot: a trailing stop that accelerates toward price as a move runs, flipping the trend reading when price crosses it.

Lagged buy & hold2021-10-06 → 2026-10-05 · 1,254 barsCosts & slippage onvs Buy & HoldHypothetical · not advice
Total return
-16.7%
Buy & hold +38.9%
vs Buy & Hold
-55.6 pts
lagged the benchmark
Max drawdown
-40.9%
Sharpe -0.12 · 59 trades
The honest read

Over this period, Parabolic SAR on T-Mobile US returned -16.7%, while simply buying and holding returned +38.9% — it lagged buy & hold by 55.6 points, with a worst drawdown of -40.9%. It traded 59 times and sat in cash about 50% of the time. It's a mechanism you test — not a recommendation.

What this settles — and the next dig

It lagged buy & hold over this window — that's a result, and a backtest you can kill for free just did its job. Re-tuning this same idea until it looks better only adds another shot at looking good by luck, so the honest next move is a fresh one: test a different strategy on T-Mobile US, or build your own — free. Most ideas die cheaply right here, and that's exactly how the rare one that holds up gets found.

Or stop here — walking away from an idea that didn't beat simply holding is a result, not a failure.

Interactive

Run it yourself

Change the parameters and the window, then re-run — no account needed.

Change the rules? Open the Parabolic SAR rules on T-Mobile US in the no-code builder — the same rules tested here — and make them your own.

Open in the builder →
Worked example

Two real trades from this backtest

Shown at the modeled fills — entries at the next open, protective stops and targets at their level; costs on. A single trade is never a signal and says nothing about the next one — not the best or worst, a middling winner and a middling loser among the completed trades.

59 trades total — 19 winners, 40 losers (32% won). Below is one of each, not a scoreboard.

  1. Entry. A long entry fired; filled at the next open on 2025-09-25 at $240.17 — never the signal bar's own close.
  2. Held. 5 daily bars.
  3. Exit. Exited on 2025-10-02 at $232.54 (the exit rule fired (filled at the next open)).
  4. Result. -3.28% after costs.

The worst single trade in this whole test reached -12.49%.

  1. Entry. A long entry fired; filled at the next open on 2023-11-17 at $147.96 — never the signal bar's own close.
  2. Held. 19 daily bars.
  3. Exit. Exited on 2023-12-15 at $156.87 (the exit rule fired (filled at the next open)).
  4. Result. +5.92% after costs.

Trading costs + slippage (0.10%) are already deducted from every figure above. One trade is never the edge — it's the whole distribution (the win rate, the losers, the reality-check) that matters; this just makes the mechanics concrete. It describes the past; it is not a prediction.

Put this honest verdict on your site

A live badge that re-runs itself and links back here. Free to embed on any blog, newsletter or forum — it shows the honest result, beat or lagged.

<iframe src="https://stratsemble.com/embed/t-mobile-parabolic-sar-backtest" width="360" height="340" style="border:0;border-radius:12px;max-width:100%" loading="lazy" title="Does the Parabolic SAR strategy beat buy & hold on T-Mobile US?"></iframe>
How to read this
  • • The strategy line is Parabolic SAR on T-Mobile US; the dashed line is simply buying and holding TMUS. Beating the dashed line is the whole point — many strategies don't.
  • • Max drawdown is the worst peak-to-trough fall you'd have sat through. A higher return with a much deeper drawdown is not obviously better.
  • • Every fill assumes next-open execution with costs & slippage on — no acting on prices you couldn't have known.
  • • A small number of trades means a small sample. Treat a great-looking result on a handful of trades with suspicion.
What this is — and isn't

This is a hypothetical backtest of a well-known mechanism on past data. It is not advice, not a prediction, and not a claim that the strategy works. I hold no funds and place no orders. The value here is the ability to test an idea honestly — see where it would have helped, and where it would have hurt — before you ever risk real money on your own broker.

How this is computed → · who's behind it · where a backtest fits

See what actually beats buy & hold — most don't, here are the rare few that do →