Group 1 Automotive Inc (GPI)
Group 1 Automotive, Inc., operates in the automotive retail industry. The company is headquartered in Houston, Texas.
Stock Price Trends
Stock price trends estimated using linear regression.
Key facts
- The primary trend is increasing.
- The growth rate of the primary trend is 44.80% per annum.
- GPI price at the close of September 29, 2025 was $437.41 and was lower than the bottom border of the primary price channel by $18.02 (3.96%). This indicates a possible reversal in the primary trend direction.
- The secondary trend is increasing.
- The growth rate of the secondary trend is 7.84% per annum.
- GPI price at the close of September 29, 2025 was inside the secondary price channel.
Linear Regression Model
Model equation:
Yi = α + β × Xi + εi
Top border of price channel:
Exp(Yi) = Exp(a + b × Xi + 2 × s)
Bottom border of price channel:
Exp(Yi) = Exp(a + b × Xi – 2 × s)
where:
i - observation number
Yi - natural logarithm of GPI price
Xi - time index, 1 day interval
σ - standard deviation of εi
a - estimator of α
b - estimator of β
s - estimator of σ
Exp() - calculates the exponent of e
Primary Trend
Start date: June 16, 2022
End date: March 12, 2025
a = 4.4223
b = 0.0010
s = 0.0760
Annual growth rate:
Exp(365 × b) – 1
= Exp(365 × 0.0010) – 1
= 44.80%
Price channel spread:
Exp(4 × s) – 1
= Exp(4 × 0.0760) – 1
= 35.52%
June 16, 2022 calculations
Top border of price channel:
Exp(Y431)
= Exp(a + b × X431 + 2 × s)
= Exp(a + b × 624 + 2 × s)
= Exp(4.4223 + 0.0010 × 624 + 2 × 0.0760)
= Exp(5.2071)
= $182.57
Bottom border of price channel:
Exp(Y431)
= Exp(a + b × X431 – 2 × s)
= Exp(a + b × 624 – 2 × s)
= Exp(4.4223 + 0.0010 × 624 – 2 × 0.0760)
= Exp(4.9032)
= $134.72
March 12, 2025 calculations
Top border of price channel:
Exp(Y1,116)
= Exp(a + b × X1,116 + 2 × s)
= Exp(a + b × 1,624 + 2 × s)
= Exp(4.4223 + 0.0010 × 1,624 + 2 × 0.0760)
= Exp(6.2213)
= $503.36
Bottom border of price channel:
Exp(Y1,116)
= Exp(a + b × X1,116 – 2 × s)
= Exp(a + b × 1,624 – 2 × s)
= Exp(4.4223 + 0.0010 × 1,624 – 2 × 0.0760)
= Exp(5.9174)
= $371.44
Description
- The primary trend is increasing.
- The growth rate of the primary trend is 44.80% per annum.
- GPI price at the close of September 29, 2025 was $437.41 and was lower than the bottom border of the primary price channel by $18.02 (3.96%). This indicates a possible reversal in the primary trend direction.
Secondary Trend
Start date: November 6, 2024
End date: September 29, 2025
a = 5.7228
b = 0.0002
s = 0.0562
Annual growth rate:
Exp(365 × b) – 1
= Exp(365 × 0.0002) – 1
= 7.84%
Price channel spread:
Exp(4 × s) – 1
= Exp(4 × 0.0562) – 1
= 25.19%
November 6, 2024 calculations
Top border of price channel:
Exp(Y1,032)
= Exp(a + b × X1,032 + 2 × s)
= Exp(a + b × 1,498 + 2 × s)
= Exp(5.7228 + 0.0002 × 1,498 + 2 × 0.0562)
= Exp(6.1448)
= $466.28
Bottom border of price channel:
Exp(Y1,032)
= Exp(a + b × X1,032 – 2 × s)
= Exp(a + b × 1,498 – 2 × s)
= Exp(5.7228 + 0.0002 × 1,498 – 2 × 0.0562)
= Exp(5.9201)
= $372.45
September 29, 2025 calculations
Top border of price channel:
Exp(Y1,254)
= Exp(a + b × X1,254 + 2 × s)
= Exp(a + b × 1,825 + 2 × s)
= Exp(5.7228 + 0.0002 × 1,825 + 2 × 0.0562)
= Exp(6.2124)
= $498.89
Bottom border of price channel:
Exp(Y1,254)
= Exp(a + b × X1,254 – 2 × s)
= Exp(a + b × 1,825 – 2 × s)
= Exp(5.7228 + 0.0002 × 1,825 – 2 × 0.0562)
= Exp(5.9877)
= $398.50
Description
- The secondary trend is increasing.
- The growth rate of the secondary trend is 7.84% per annum.
- GPI price at the close of September 29, 2025 was inside the secondary price channel.