Quidel Corporation (QDEL)
Quidel Corporation is a leading provider of diagnostic testing solutions, focusing on infectious diseases, cardiology, women's health, and other critical health areas. Headquartered in San Diego, California, Quidel combines innovative technology with a vast global distribution network to deliver rapid and accurate diagnostic products. With a commitment to improving patient outcomes, the company plays a vital role in enhancing healthcare solutions through its extensive product offerings and continuous development in the diagnostics sector.
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 6.91% per annum.
- QDEL price at the close of February 12, 2026 was $23.74 and was lower than the bottom border of the primary price channel by $43.71 (64.80%).
- The secondary trend is decreasing.
- The decline rate of the secondary trend is 38.43% per annum.
- QDEL price at the close of February 12, 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 QDEL 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: January 19, 2023
End date: August 7, 2023
a = 4.6229
b = -0.0002
s = 0.0270
Annual growth rate:
Exp(365 × b) – 1
= Exp(365 × -0.0002) – 1
= -6.91%
Price channel spread:
Exp(4 × s) – 1
= Exp(4 × 0.0270) – 1
= 11.41%
January 19, 2023 calculations
Top border of price channel:
Exp(Y485)
= Exp(a + b × X485 + 2 × s)
= Exp(a + b × 702 + 2 × s)
= Exp(4.6229 + -0.0002 × 702 + 2 × 0.0270)
= Exp(4.5392)
= $93.61
Bottom border of price channel:
Exp(Y485)
= Exp(a + b × X485 – 2 × s)
= Exp(a + b × 702 – 2 × s)
= Exp(4.6229 + -0.0002 × 702 – 2 × 0.0270)
= Exp(4.4311)
= $84.03
August 7, 2023 calculations
Top border of price channel:
Exp(Y622)
= Exp(a + b × X622 + 2 × s)
= Exp(a + b × 902 + 2 × s)
= Exp(4.6229 + -0.0002 × 902 + 2 × 0.0270)
= Exp(4.4999)
= $90.01
Bottom border of price channel:
Exp(Y622)
= Exp(a + b × X622 – 2 × s)
= Exp(a + b × 902 – 2 × s)
= Exp(4.6229 + -0.0002 × 902 – 2 × 0.0270)
= Exp(4.3919)
= $80.79
Description
- The primary trend is decreasing.
- The decline rate of the primary trend is 6.91% per annum.
- QDEL price at the close of February 12, 2026 was $23.74 and was lower than the bottom border of the primary price channel by $43.71 (64.80%).
Secondary Trend
Start date: January 19, 2023
End date: December 9, 2025
a = 5.4953
b = -0.0013
s = 0.1381
Annual growth rate:
Exp(365 × b) – 1
= Exp(365 × -0.0013) – 1
= -38.43%
Price channel spread:
Exp(4 × s) – 1
= Exp(4 × 0.1381) – 1
= 73.71%
January 19, 2023 calculations
Top border of price channel:
Exp(Y485)
= Exp(a + b × X485 + 2 × s)
= Exp(a + b × 702 + 2 × s)
= Exp(5.4953 + -0.0013 × 702 + 2 × 0.1381)
= Exp(4.8388)
= $126.32
Bottom border of price channel:
Exp(Y485)
= Exp(a + b × X485 – 2 × s)
= Exp(a + b × 702 – 2 × s)
= Exp(5.4953 + -0.0013 × 702 – 2 × 0.1381)
= Exp(4.2866)
= $72.72
December 9, 2025 calculations
Top border of price channel:
Exp(Y1,210)
= Exp(a + b × X1,210 + 2 × s)
= Exp(a + b × 1,757 + 2 × s)
= Exp(5.4953 + -0.0013 × 1,757 + 2 × 0.1381)
= Exp(3.4372)
= $31.10
Bottom border of price channel:
Exp(Y1,210)
= Exp(a + b × X1,210 – 2 × s)
= Exp(a + b × 1,757 – 2 × s)
= Exp(5.4953 + -0.0013 × 1,757 – 2 × 0.1381)
= Exp(2.8850)
= $17.90
Description
- The secondary trend is decreasing.
- The decline rate of the secondary trend is 38.43% per annum.
- QDEL price at the close of February 12, 2026 was inside the secondary price channel.