Westport Fuel Systems (STU:WPI) Shiller PE Ratio: (As of Sep. 21, 2026)

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STU:WPI Westport Fuel Systems Inc STU:WPI
40 GF Score
Price €1.66
GF Value €0.42
Valuation Significantly Overvalued
! 7 Warning Signs
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What is Westport Fuel Systems Shiller PE Ratio?

Shiller PE for Stocks: The True Measure of Stock Valuation


Westport Fuel Systems  (STU:WPI) Shiller PE Ratio Explanation

Compared with the regular PE Ratio, which works poorly for cyclical businesses, the Shiller PE Ratio smoothed out the fluctuations of profit margins during business cycles. Therefore it is more accurate in reflecting the valuation of the company.

If a company has consistent business performance, the Shiller PE Ratio should give similar results to regular PE Ratio.

Compared with the PS Ratio, the Shiller PE Ratio makes the comparison between different industries more meaningful.


Be Aware

Shiller PE Ratio assumes that over the long term, businesses and profitability revert to their means. If a company's business model does not work in the future compared with the past, Shiller PE Ratio and PS Ratio will give false valuations.


Westport Fuel Systems Shiller PE Ratio Related Terms


Westport Fuel Systems Shiller PE Ratio Historical Data

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The historical data trend for Westport Fuel Systems's Shiller PE Ratio can be seen below:

* For Operating Data section: All numbers are indicated by the unit behind each term and all currency related amount are in USD.
* For other sections: All numbers are in millions except for per share data, ratio, and percentage. All currency related amount are indicated in the company's associated stock exchange currency.

Westport Fuel Systems Shiller PE Ratio Chart

Westport Fuel Systems Annual Data
Trend Dec16 Dec17 Dec18 Dec19 Dec20 Dec21 Dec22 Dec23 Dec24 Dec25
Shiller PE Ratio
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Westport Fuel Systems Quarterly Data
Sep21 Dec21 Mar22 Jun22 Sep22 Dec22 Mar23 Jun23 Sep23 Dec23 Mar24 Jun24 Sep24 Dec24 Mar25 Jun25 Sep25 Dec25 Mar26 Jun26
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STU:WPI vs ORLY, AZO, GPC: Shiller PE Ratio Comparison

For the Auto Parts subindustry, Westport Fuel Systems's Shiller PE Ratio, along with its competitors' market caps and Shiller PE Ratio data, can be viewed below:

* Competitive companies are chosen from companies within the same industry, with headquarter located in same country, with closest market capitalization; x-axis shows the market cap, and y-axis shows the term value; the bigger the dot, the larger the market cap. Note that "N/A" values will not show up in the chart.


Westport Fuel Systems Shiller PE Ratio vs Vehicles & Parts Industry

For the Vehicles & Parts industry and Consumer Cyclical sector, Westport Fuel Systems's Shiller PE Ratio distribution charts can be found below:

* The bar in red indicates where Westport Fuel Systems's Shiller PE Ratio falls into.


STU:WPI
40GF Score
Westport Fuel Systems Inc STU:WPI
Shiller PE Ratio is just one metric. See GF Score™, valuation, warning signs, and more.
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Westport Fuel Systems Shiller PE Ratio Calculation

For Shiller PE Ratio, the earnings of the past 10 years are inflation-adjusted and averaged. The result is used for P/E calculation. Since it looks at the average over the last 10 years, the Shiller PE Ratio is also called PE10.

The Shiller PE Ratio was first used by professor Robert Shiller to measure the valuation of the overall market. The same calculation is applied here to individual companies.

Westport Fuel Systems's E10 for the quarter that ended in Jun. 2026 is calculated as:

For example, Westport Fuel Systems's adjusted earnings per share data for the three months ended in Jun. 2026 was:

Adj_EPS=Earnings per Share (Diluted)/CPI of Jun. 2026 (Change)*Current CPI (Jun. 2026)
=-0.5489/133.5265*133.5265
=-0.549

Current CPI (Jun. 2026) = 133.5265.

Westport Fuel Systems Quarterly Data

Earnings per Share (Diluted) CPI Adj_EPS
201609 -2.629 101.765 -3.449
201612 -3.750 101.449 -4.935
201703 -1.032 102.634 -1.343
201706 -1.860 103.029 -2.411
201709 -1.206 103.345 -1.559
201712 -1.133 103.345 -1.464
201803 -0.880 105.004 -1.120
201806 -0.336 105.557 -0.425
201809 -0.848 105.636 -1.072
201812 -0.605 105.399 -0.766
201903 -0.201 106.979 -0.250
201906 -0.170 107.690 -0.211
201909 0.335 107.611 0.416
201912 0.043 107.769 0.054
202003 -1.017 107.927 -1.259
202006 0.186 108.401 0.228
202009 0.048 108.164 0.060
202012 0.241 108.559 0.296
202103 -0.177 110.298 -0.215
202106 0.912 111.720 1.090
202109 -0.289 112.905 -0.341
202112 0.270 113.774 0.317
202203 0.394 117.646 0.447
202206 -0.635 120.806 -0.701
202209 -0.692 120.648 -0.765
202212 -0.968 120.964 -1.068
202303 -0.577 122.702 -0.628
202306 -0.707 124.203 -0.760
202309 -0.621 125.230 -0.662
202312 -0.755 125.072 -0.806
202403 -0.730 126.258 -0.772
202406 0.309 127.522 0.324
202409 -0.204 127.285 -0.214
202412 -0.550 127.364 -0.577
202503 -0.327 129.181 -0.338
202506 -1.748 129.892 -1.796
202509 -0.426 130.287 -0.437
202512 -0.448 130.366 -0.459
202603 -0.280 132.262 -0.283
202606 -0.549 133.527 -0.549

Add all the adjusted EPS together and divide 10 will get our E10.

Please note that we use the CPI data of the country/region where the company is headquartered. If the CPI data for that country/region is not available, then we will use the CPI data of the United States as default.

Is Westport Fuel Systems (STU:WPI) Overvalued in 2026?

Based on GuruFocus' analysis, Westport Fuel Systems stock appears to be overvalued. The current stock price of €1.66 is trading 295.2% above its estimated GF Value™ of €0.42. GuruFocus considers Westport Fuel Systems to be Significantly Overvalued.

Key valuation signals for STU:WPI:

  • Shiller PE Ratio:
  • GF Value™: €0.42 vs. price of €1.66 (295.2% above fair value)
  • GF Score™: 40/100 with 7 warning signs

No single metric tells the full story. See the STU:WPI stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.


Westport Fuel Systems Business Description

Address 1691 West 75th Avenue, Suite 101, Vancouver, BC, CAN, V6P 6P2
Westport Fuel Systems Inc is an organization engaged in the engineering, manufacturing, and supply of alternative fuel systems and components for transportation applications. It has three reportable segments: High-Pressure Controls, Heavy-Duty OEM, and Cespira. It derives maximum revenue from Heavy-Duty OEM segment. Heavy-Duty OEM segment's products include HPDI related fuel system solutions and components. Geographically, the company operates in Europe, America and Asia, of which it generates maximum revenue from Europe. It also develops and supplies advanced LPG, CNG, LNG and H2 systems and components for OEM (original equipment manufacturer) D-OEM (delayed oem) and After Market (retrofit market) world-wide.
40GF Score

Get the complete analysis for STU:WPI

Shiller PE Ratio is just one metric. See GF Value™, 30-year financials, guru trades, warning signs, and more.

€1.66
Price
€0.42
GF Value