SO vs. PFE

Last updated Jun 6, 2026

SO (The Southern Company) and PFE (Pfizer Inc.) are both stocks. SO operates in Utilities - Regulated Electric (Utilities), while PFE operates in Drug Manufacturers - General (Healthcare). Over the past 10 years, SO returned 10.83%/yr vs 2.09%/yr for PFE. At a 0.26 correlation, their price movements are largely independent.

Performance

SO vs. PFE - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in The Southern Company (SO) and Pfizer Inc. (PFE). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

The year-to-date returns for both investments are quite close, with SO having a 7.91% return and PFE slightly higher at 8.09%. Over the past 10 years, SO has outperformed PFE with an annualized return of 10.83%, while PFE has yielded a comparatively lower 2.09% annualized return.

SO

• 1D: 1.07%
• 1M: 1.71%
• YTD: 7.91%
• 6M: 9.06%
• 1Y: 8.35%
• 3Y*: 14.05%
• 5Y*: 11.60%
• 10Y*: 10.83%

PFE

• 1D: 1.36%
• 1M: 1.40%
• YTD: 8.09%
• 6M: 3.39%
• 1Y: 19.31%
• 3Y*: -6.48%
• 5Y*: -2.98%
• 10Y*: 2.09%

*Multi-year figures are annualized to reflect compound growth (CAGR)

SO vs. PFE - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
SO The Southern Company	7.91%	9.47%	21.72%	2.21%	8.24%	16.34%	0.63%	51.65%	-3.75%	2.42%
PFE Pfizer Inc.	8.09%	0.65%	-2.22%	-41.26%	-10.41%	66.70%	3.07%	-6.91%	24.82%	15.90%

Correlation

The correlation between SO and PFE is 0.18, which is low. Their price movements are largely independent, making them effective diversification partners.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.18
Correlation (3Y) Calculated over the trailing 3-year period	0.27
Correlation (5Y) Calculated over the trailing 5-year period	0.30
Correlation (10Y) Calculated over the trailing 10-year period	0.28
Correlation (All Time) Calculated using the full available price history since Jan 4, 1982	0.26

The correlation between SO and PFE shifts across timeframes, from 0.18 (1 year) to 0.30 (5 years), reflecting how their relationship changes across market environments.

Fundamentals

Market Cap SO : $104.45B PFE : $149.24B
EPS SO : $3.92 PFE : $1.31
PE Ratio SO : 23.62 PFE : 19.85
PEG Ratio SO : 1.46 PFE : 0.36
PS Ratio SO : 3.42 PFE : 2.35
PB Ratio SO : 2.81 PFE : 1.66
Total Revenue (TTM) SO : $30.17B PFE : $63.32B
Gross Profit (TTM) SO : $13.01B PFE : $43.91B
EBITDA (TTM) SO : $14.44B PFE : $16.94B

Return for Risk

SO vs. PFE — Risk / Return Rank

Compare risk-adjusted metric ranks to identify better-performing investments over the past 12 months.

SO

SO Risk / Return Rank: 54
SO Sharpe Ratio Rank: 59
SO Sortino Ratio Rank: 51
SO Omega Ratio Rank: 49
SO Calmar Ratio Rank: 54
SO Martin Ratio Rank: 55

PFE

PFE Risk / Return Rank: 67
PFE Sharpe Ratio Rank: 68
PFE Sortino Ratio Rank: 64
PFE Omega Ratio Rank: 61
PFE Calmar Ratio Rank: 72
PFE Martin Ratio Rank: 70

The rank (0–100) shows how this investment's returns compare to the risk taken. Higher = better. Based on the past 12 months of data, combining Sharpe, Sortino, and other metrics used by quantitative funds and institutional investors.

SO vs. PFE - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for The Southern Company (SO) and Pfizer Inc. (PFE). Risk-adjusted metrics are performance indicators that assess an investment's returns in relation to its risk, enabling a more accurate comparison of different investment options.

	SO	PFE	Difference
Sharpe ratio: Return per unit of total volatility	0.52	0.86	-0.35
Sortino ratio: Return per unit of downside risk	0.84	1.43	-0.58
Omega ratio: Gain probability vs. loss probability	1.10	1.17	-0.07
Calmar ratio: Return relative to maximum drawdown	0.55	1.79	-1.25
Martin ratio: Return relative to average drawdown	1.29	3.68	-2.38
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

SO vs. PFE - Sharpe Ratio Comparison

The current SO Sharpe Ratio is 0.52, which is lower than the PFE Sharpe Ratio of 0.86. The chart below compares the historical Sharpe Ratios of SO and PFE, calculated using daily returns over the previous 12 months. A higher Sharpe Ratio indicates better risk-adjusted performance relative to the risk-free rate.

Sharpe Ratios by Period

	SO	PFE	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	0.52	0.86	-0.35
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.62	-0.12	+0.74
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.49	0.09	+0.41
Sharpe Ratio (All Time) Calculated using the full available price history	0.62	0.33	+0.29

Drawdowns

SO vs. PFE - Drawdown Comparison

The maximum SO drawdown since its inception was -38.43%, smaller than the maximum PFE drawdown of -69.24%. Use the drawdown chart below to compare losses from any high point for SO and PFE.

Drawdown Indicators

	SO	PFE	Difference
Max Drawdown Largest peak-to-trough decline	-38.43%	-69.24%	+30.81%
Max Drawdown (1Y) Largest decline over 1 year	-14.99%	-11.47%	-3.52%
Max Drawdown (3Y) Largest decline over 3 years	-14.99%	-40.75%	+25.76%
Max Drawdown (5Y) Largest decline over 5 years	-23.28%	-58.96%	+35.68%
Max Drawdown (10Y) Largest decline over 10 years	-38.43%	-58.96%	+20.53%
Current Drawdown Current decline from peak	-5.79%	-46.03%	+40.24%
Average Drawdown Average peak-to-trough decline	-6.87%	-22.89%	+16.02%
Ulcer Index Depth and duration of drawdowns from previous peaks	6.35%	5.59%	+0.76%

Volatility

SO vs. PFE - Volatility Comparison

The Southern Company (SO) has a higher volatility of 5.62% compared to Pfizer Inc. (PFE) at 4.50%. This indicates that SO's price experiences larger fluctuations and is considered to be riskier than PFE based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	SO	PFE	Difference
Volatility (1M) Calculated over the trailing 1-month period	5.62%	4.50%	+1.12%
Volatility (6M) Calculated over the trailing 6-month period	12.98%	14.66%	-1.68%
Volatility (1Y) Calculated over the trailing 1-year period	15.97%	23.92%	-7.95%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	18.65%	25.50%	-6.85%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	21.94%	23.88%	-1.94%

Dividends

SO vs. PFE - Dividend Comparison

SO's dividend yield for the trailing twelve months is around 3.22%, less than PFE's 6.61% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
PFE Pfizer Inc.	6.61%	6.91%	6.33%	5.70%	3.12%	2.64%	3.92%	3.68%	3.12%	3.53%	3.69%	3.47%
SO The Southern Company	3.22%	3.37%	3.47%	3.96%	3.78%	3.82%	4.13%	3.86%	5.42%	4.78%	4.52%	4.60%

Financials

SO vs. PFE - Profitability Comparison

The chart below illustrates the profitability comparison between The Southern Company and Pfizer Inc. over time, highlighting three key metrics: Gross Profit Margin, Operating Margin, and Net Profit Margin.

SO - Gross Margin

Gross margin is calculated as gross profit divided by revenue. For the three months ending on Jun 2026, The Southern Company reported a gross profit of 3.90B and revenue of 8.40B. Therefore, the gross margin over that period was 46.5%.

PFE - Gross Margin

Gross margin is calculated as gross profit divided by revenue. For the three months ending on Jun 2026, Pfizer Inc. reported a gross profit of 9.72B and revenue of 14.45B. Therefore, the gross margin over that period was 67.3%.

SO - Operating Margin

Operating margin is calculated as operating income divided by revenue. For the three months ending on Jun 2026, The Southern Company reported an operating income of 2.02B and revenue of 8.40B, resulting in an operating margin of 24.0%.

PFE - Operating Margin

Operating margin is calculated as operating income divided by revenue. For the three months ending on Jun 2026, Pfizer Inc. reported an operating income of 4.03B and revenue of 14.45B, resulting in an operating margin of 27.9%.

SO - Net Margin

Net margin is calculated as net income divided by revenue. For the three months ending on Jun 2026, The Southern Company reported a net income of 1.36B and revenue of 8.40B, resulting in a net margin of 16.2%.

PFE - Net Margin

Net margin is calculated as net income divided by revenue. For the three months ending on Jun 2026, Pfizer Inc. reported a net income of 2.69B and revenue of 14.45B, resulting in a net margin of 18.6%.

Frequently Asked Questions

Can I hold both SO and PFE in my portfolio?

SO and PFE have a correlation of 0.18, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, SO or PFE?

SO has higher volatility (5.62%) compared to PFE (4.50%). In terms of maximum drawdown, SO dropped -38.43% vs PFE's -69.24%.

Which has better risk-adjusted returns?

PFE currently has the higher Sharpe Ratio (0.86 vs 0.52), meaning it's delivered slightly more return per unit of risk over the trailing 12 months. However, this ranking shifts over time - use the Risk/Return Score above for a more comprehensive view that combines Sharpe, Sortino, and other measures used by quantitative funds.