Stock Price Trends

Duolingo Inc (DUOL)

None

Stock Price Trends

Stock price trends estimated using linear regression.

Key facts

  • The primary trend is decreasing.
  • The decline rate of the primary trend is 82.14% per annum.
  • DUOL price at the close of January 22, 2026 was $153.70 and was inside the primary price channel.
  • The secondary trend is decreasing.
  • The decline rate of the secondary trend is 55.57% per annum.
  • DUOL price at the close of January 22, 2026 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 DUOL 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: May 2, 2025
End date: January 22, 2026

a = 12.8153

b = -0.0047

s = 0.1108

Annual growth rate:

Exp(365 × b) – 1
= Exp(365 × -0.0047) – 1
= -82.14%

Price channel spread:

Exp(4 × s) – 1
= Exp(4 × 0.1108) – 1
= 55.75%

May 2, 2025 calculations

Top border of price channel:

Exp(Y945)
= Exp(a + b × X945 + 2 × s)
= Exp(a + b × 1,374 + 2 × s)
= Exp(12.8153 + -0.0047 × 1,374 + 2 × 0.1108)
= Exp(6.5513)
= $700.19

Bottom border of price channel:

Exp(Y945)
= Exp(a + b × X945 – 2 × s)
= Exp(a + b × 1,374 – 2 × s)
= Exp(12.8153 + -0.0047 × 1,374 – 2 × 0.1108)
= Exp(6.1082)
= $449.55

January 22, 2026 calculations

Top border of price channel:

Exp(Y1,126)
= Exp(a + b × X1,126 + 2 × s)
= Exp(a + b × 1,639 + 2 × s)
= Exp(12.8153 + -0.0047 × 1,639 + 2 × 0.1108)
= Exp(5.3005)
= $200.44

Bottom border of price channel:

Exp(Y1,126)
= Exp(a + b × X1,126 – 2 × s)
= Exp(a + b × 1,639 – 2 × s)
= Exp(12.8153 + -0.0047 × 1,639 – 2 × 0.1108)
= Exp(4.8574)
= $128.69

Description

  • The primary trend is decreasing.
  • The decline rate of the primary trend is 82.14% per annum.
  • DUOL price at the close of January 22, 2026 was $153.70 and was inside the primary price channel.

Secondary Trend

Start date: November 6, 2025
End date: January 22, 2026

a = 8.7485

b = -0.0022

s = 0.0648

Annual growth rate:

Exp(365 × b) – 1
= Exp(365 × -0.0022) – 1
= -55.57%

Price channel spread:

Exp(4 × s) – 1
= Exp(4 × 0.0648) – 1
= 29.58%

November 6, 2025 calculations

Top border of price channel:

Exp(Y1,075)
= Exp(a + b × X1,075 + 2 × s)
= Exp(a + b × 1,562 + 2 × s)
= Exp(8.7485 + -0.0022 × 1,562 + 2 × 0.0648)
= Exp(5.4061)
= $222.77

Bottom border of price channel:

Exp(Y1,075)
= Exp(a + b × X1,075 – 2 × s)
= Exp(a + b × 1,562 – 2 × s)
= Exp(8.7485 + -0.0022 × 1,562 – 2 × 0.0648)
= Exp(5.1470)
= $171.91

January 22, 2026 calculations

Top border of price channel:

Exp(Y1,126)
= Exp(a + b × X1,126 + 2 × s)
= Exp(a + b × 1,639 + 2 × s)
= Exp(8.7485 + -0.0022 × 1,639 + 2 × 0.0648)
= Exp(5.2350)
= $187.72

Bottom border of price channel:

Exp(Y1,126)
= Exp(a + b × X1,126 – 2 × s)
= Exp(a + b × 1,639 – 2 × s)
= Exp(8.7485 + -0.0022 × 1,639 – 2 × 0.0648)
= Exp(4.9758)
= $144.87

Description

  • The secondary trend is decreasing.
  • The decline rate of the secondary trend is 55.57% per annum.
  • DUOL price at the close of January 22, 2026 was inside the secondary price channel.