Stock Price Trends

DexCom Inc (DXCM)

DexCom, Inc. is a company that develops, manufactures, and distributes continuous glucose monitoring (CGM) systems for diabetes management. It operates internationally with headquarters in San Diego, California, and has a manufacturing facility in Mesa, Arizona.

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 40.71% per annum.
  • DXCM price at the close of April 29, 2025 was $71.30 and was inside the primary price channel.
  • The secondary trend is increasing.
  • The growth rate of the secondary trend is 11.92% per annum.
  • DXCM price at the close of April 29, 2025 was inside the secondary price channel.
  • The direction of the secondary trend is opposite to the direction of the primary trend. This indicates a possible reversal in the direction of the primary trend.

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 DXCM 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: November 29, 2023
End date: April 29, 2025

a = 6.7880

b = -0.0014

s = 0.1580

Annual growth rate:

Exp(365 × b) – 1
= Exp(365 × -0.0014) – 1
= -40.71%

Price channel spread:

Exp(4 × s) – 1
= Exp(4 × 0.1580) – 1
= 88.15%

November 29, 2023 calculations

Top border of price channel:

Exp(Y902)
= Exp(a + b × X902 + 2 × s)
= Exp(a + b × 1,308 + 2 × s)
= Exp(6.7880 + -0.0014 × 1,308 + 2 × 0.1580)
= Exp(5.2306)
= $186.91

Bottom border of price channel:

Exp(Y902)
= Exp(a + b × X902 – 2 × s)
= Exp(a + b × 1,308 – 2 × s)
= Exp(6.7880 + -0.0014 × 1,308 – 2 × 0.1580)
= Exp(4.5985)
= $99.34

April 29, 2025 calculations

Top border of price channel:

Exp(Y1,255)
= Exp(a + b × X1,255 + 2 × s)
= Exp(a + b × 1,825 + 2 × s)
= Exp(6.7880 + -0.0014 × 1,825 + 2 × 0.1580)
= Exp(4.4901)
= $89.13

Bottom border of price channel:

Exp(Y1,255)
= Exp(a + b × X1,255 – 2 × s)
= Exp(a + b × 1,825 – 2 × s)
= Exp(6.7880 + -0.0014 × 1,825 – 2 × 0.1580)
= Exp(3.8581)
= $47.37

Description

  • The primary trend is decreasing.
  • The decline rate of the primary trend is 40.71% per annum.
  • DXCM price at the close of April 29, 2025 was $71.30 and was inside the primary price channel.

Secondary Trend

Start date: July 26, 2024
End date: April 29, 2025

a = 3.7901

b = 0.0003

s = 0.0909

Annual growth rate:

Exp(365 × b) – 1
= Exp(365 × 0.0003) – 1
= 11.92%

Price channel spread:

Exp(4 × s) – 1
= Exp(4 × 0.0909) – 1
= 43.82%

July 26, 2024 calculations

Top border of price channel:

Exp(Y1,066)
= Exp(a + b × X1,066 + 2 × s)
= Exp(a + b × 1,548 + 2 × s)
= Exp(3.7901 + 0.0003 × 1,548 + 2 × 0.0909)
= Exp(4.4494)
= $85.58

Bottom border of price channel:

Exp(Y1,066)
= Exp(a + b × X1,066 – 2 × s)
= Exp(a + b × 1,548 – 2 × s)
= Exp(3.7901 + 0.0003 × 1,548 – 2 × 0.0909)
= Exp(4.0860)
= $59.50

April 29, 2025 calculations

Top border of price channel:

Exp(Y1,255)
= Exp(a + b × X1,255 + 2 × s)
= Exp(a + b × 1,825 + 2 × s)
= Exp(3.7901 + 0.0003 × 1,825 + 2 × 0.0909)
= Exp(4.5349)
= $93.21

Bottom border of price channel:

Exp(Y1,255)
= Exp(a + b × X1,255 – 2 × s)
= Exp(a + b × 1,825 – 2 × s)
= Exp(3.7901 + 0.0003 × 1,825 – 2 × 0.0909)
= Exp(4.1715)
= $64.81

Description

  • The secondary trend is increasing.
  • The growth rate of the secondary trend is 11.92% per annum.
  • DXCM price at the close of April 29, 2025 was inside the secondary price channel.