Stock Price Trends

Century Aluminum Company (CENX)

Century Aluminum Company produces standard quality and value-added primary aluminum products in the United States and Iceland. The company is headquartered in Chicago, Illinois.

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 46.07% per annum.
  • CENX price at the close of August 29, 2025 was $22.33 and was inside the primary price channel.
  • The secondary trend is increasing.
  • The growth rate of the secondary trend is 198.75% per annum.
  • CENX price at the close of August 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 CENX 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 23, 2022
End date: August 29, 2025

a = 1.1843

b = 0.0010

s = 0.2067

Annual growth rate:

Exp(365 × b) – 1
= Exp(365 × 0.0010) – 1
= 46.07%

Price channel spread:

Exp(4 × s) – 1
= Exp(4 × 0.2067) – 1
= 128.56%

June 23, 2022 calculations

Top border of price channel:

Exp(Y456)
= Exp(a + b × X456 + 2 × s)
= Exp(a + b × 661 + 2 × s)
= Exp(1.1843 + 0.0010 × 661 + 2 × 0.2067)
= Exp(2.2839)
= $9.81

Bottom border of price channel:

Exp(Y456)
= Exp(a + b × X456 – 2 × s)
= Exp(a + b × 661 – 2 × s)
= Exp(1.1843 + 0.0010 × 661 – 2 × 0.2067)
= Exp(1.4572)
= $4.29

August 29, 2025 calculations

Top border of price channel:

Exp(Y1,255)
= Exp(a + b × X1,255 + 2 × s)
= Exp(a + b × 1,824 + 2 × s)
= Exp(1.1843 + 0.0010 × 1,824 + 2 × 0.2067)
= Exp(3.4913)
= $32.83

Bottom border of price channel:

Exp(Y1,255)
= Exp(a + b × X1,255 – 2 × s)
= Exp(a + b × 1,824 – 2 × s)
= Exp(1.1843 + 0.0010 × 1,824 – 2 × 0.2067)
= Exp(2.6647)
= $14.36

Description

  • The primary trend is increasing.
  • The growth rate of the primary trend is 46.07% per annum.
  • CENX price at the close of August 29, 2025 was $22.33 and was inside the primary price channel.

Secondary Trend

Start date: April 4, 2025
End date: August 29, 2025

a = -2.3287

b = 0.0030

s = 0.0589

Annual growth rate:

Exp(365 × b) – 1
= Exp(365 × 0.0030) – 1
= 198.75%

Price channel spread:

Exp(4 × s) – 1
= Exp(4 × 0.0589) – 1
= 26.56%

April 4, 2025 calculations

Top border of price channel:

Exp(Y1,154)
= Exp(a + b × X1,154 + 2 × s)
= Exp(a + b × 1,677 + 2 × s)
= Exp(-2.3287 + 0.0030 × 1,677 + 2 × 0.0589)
= Exp(2.8175)
= $16.73

Bottom border of price channel:

Exp(Y1,154)
= Exp(a + b × X1,154 – 2 × s)
= Exp(a + b × 1,677 – 2 × s)
= Exp(-2.3287 + 0.0030 × 1,677 – 2 × 0.0589)
= Exp(2.5819)
= $13.22

August 29, 2025 calculations

Top border of price channel:

Exp(Y1,255)
= Exp(a + b × X1,255 + 2 × s)
= Exp(a + b × 1,824 + 2 × s)
= Exp(-2.3287 + 0.0030 × 1,824 + 2 × 0.0589)
= Exp(3.2582)
= $26.00

Bottom border of price channel:

Exp(Y1,255)
= Exp(a + b × X1,255 – 2 × s)
= Exp(a + b × 1,824 – 2 × s)
= Exp(-2.3287 + 0.0030 × 1,824 – 2 × 0.0589)
= Exp(3.0227)
= $20.55

Description

  • The secondary trend is increasing.
  • The growth rate of the secondary trend is 198.75% per annum.
  • CENX price at the close of August 29, 2025 was inside the secondary price channel.