STK vs. BSTZ

Last updated Jun 9, 2026

STK (Columbia Seligman Premium Technology Growth Closed Fund) is Technology Equities fund actively managed by Aberdeen, while BSTZ (BlackRock Science and Technology Trust II) is a stock. Over the past 5 years, STK returned 19.22%/yr vs 5.44%/yr for BSTZ. A 0.69 correlation means they provide meaningful diversification when combined.

Performance

STK vs. BSTZ - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Columbia Seligman Premium Technology Growth Closed Fund (STK) and BlackRock Science and Technology Trust II (BSTZ). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, STK achieves a 43.31% return, which is significantly higher than BSTZ's 35.52% return.

STK

• 1D: 1.22%
• 1M: 2.00%
• YTD: 43.31%
• 6M: 39.67%
• 1Y: 90.56%
• 3Y*: 31.90%
• 5Y*: 19.22%
• 10Y*: 23.37%

BSTZ

• 1D: 1.93%
• 1M: 6.46%
• YTD: 35.52%
• 6M: 37.09%
• 1Y: 68.99%
• 3Y*: 32.24%
• 5Y*: 5.44%
• 10Y*: —

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

STK vs. BSTZ - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019
STK Columbia Seligman Premium Technology Growth Closed Fund	43.31%	24.85%	17.74%	46.60%	-30.36%	48.63%	25.39%	23.10%
BSTZ BlackRock Science and Technology Trust II	35.52%	25.06%	37.49%	18.72%	-55.34%	12.71%	87.46%	4.20%

Correlation

The correlation between STK and BSTZ is 0.71, which is moderate. They share some common price drivers but move independently often enough to provide real diversification benefit when combined.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.71
Correlation (3Y) Calculated over the trailing 3-year period	0.70
Correlation (5Y) Calculated over the trailing 5-year period	0.72
Correlation (All Time) Calculated using the full available price history since Jun 27, 2019	0.69

The correlation between STK and BSTZ has been stable across timeframes, ranging from 0.69 to 0.72 - a consistent structural relationship.

Return for Risk

STK vs. BSTZ — Risk / Return Rank

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

STK

STK Risk / Return Rank: 94
STK Sharpe Ratio Rank: 98
STK Sortino Ratio Rank: 87
STK Omega Ratio Rank: 88
STK Calmar Ratio Rank: 97
STK Martin Ratio Rank: 98

BSTZ

BSTZ Risk / Return Rank: 95
BSTZ Sharpe Ratio Rank: 95
BSTZ Sortino Ratio Rank: 93
BSTZ Omega Ratio Rank: 93
BSTZ Calmar Ratio Rank: 96
BSTZ Martin Ratio Rank: 97

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.

STK vs. BSTZ - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Columbia Seligman Premium Technology Growth Closed Fund (STK) and BlackRock Science and Technology Trust II (BSTZ). 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.

	STK	BSTZ	Difference
Sharpe ratio: Return per unit of total volatility	3.64	2.96	+0.68
Sortino ratio: Return per unit of downside risk	4.06	3.57	+0.49
Omega ratio: Gain probability vs. loss probability	1.60	1.49	+0.11
Calmar ratio: Return relative to maximum drawdown	7.09	7.49	-0.40
Martin ratio: Return relative to average drawdown	28.46	23.14	+5.32
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

STK vs. BSTZ - Sharpe Ratio Comparison

The current STK Sharpe Ratio is 3.64, which is comparable to the BSTZ Sharpe Ratio of 2.96. The chart below compares the historical Sharpe Ratios of STK and BSTZ, 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

	STK	BSTZ	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	3.64	2.96	+0.68
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.76	0.20	+0.56
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.89	—	—
Sharpe Ratio (All Time) Calculated using the full available price history	0.72	0.51	+0.21

Drawdowns

STK vs. BSTZ - Drawdown Comparison

The maximum STK drawdown since its inception was -41.74%, smaller than the maximum BSTZ drawdown of -60.51%. Use the drawdown chart below to compare losses from any high point for STK and BSTZ.

Drawdown Indicators

	STK	BSTZ	Difference
Max Drawdown Largest peak-to-trough decline	-41.74%	-60.51%	+18.77%
Max Drawdown (1Y) Largest decline over 1 year	-12.84%	-9.26%	-3.58%
Max Drawdown (3Y) Largest decline over 3 years	-26.59%	-25.31%	-1.28%
Max Drawdown (5Y) Largest decline over 5 years	-36.27%	-60.51%	+24.24%
Max Drawdown (10Y) Largest decline over 10 years	-41.74%	—	—
Current Drawdown Current decline from peak	-10.49%	-6.18%	-4.31%
Average Drawdown Average peak-to-trough decline	-7.41%	-27.52%	+20.11%
Ulcer Index Depth and duration of drawdowns from previous peaks	3.19%	2.99%	+0.20%

Volatility

STK vs. BSTZ - Volatility Comparison

Columbia Seligman Premium Technology Growth Closed Fund (STK) has a higher volatility of 13.52% compared to BlackRock Science and Technology Trust II (BSTZ) at 11.24%. This indicates that STK's price experiences larger fluctuations and is considered to be riskier than BSTZ based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	STK	BSTZ	Difference
Volatility (1M) Calculated over the trailing 1-month period	13.52%	11.24%	+2.28%
Volatility (6M) Calculated over the trailing 6-month period	21.67%	20.16%	+1.51%
Volatility (1Y) Calculated over the trailing 1-year period	25.09%	23.51%	+1.58%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	25.48%	27.63%	-2.15%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	26.32%	30.24%	-3.92%

Dividends

STK vs. BSTZ - Dividend Comparison

STK's dividend yield for the trailing twelve months is around 5.26%, less than BSTZ's 8.52% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
BSTZ BlackRock Science and Technology Trust II	8.52%	12.46%	9.75%	10.90%	14.73%	5.14%	3.42%	2.44%	0.00%	0.00%	0.00%	0.00%
STK Columbia Seligman Premium Technology Growth Closed Fund	5.26%	7.38%	16.02%	6.70%	12.62%	8.48%	6.79%	7.86%	14.88%	11.82%	9.87%	10.32%

Frequently Asked Questions

Can I hold both STK and BSTZ in my portfolio?

STK and BSTZ have a correlation of 0.71, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, STK or BSTZ?

STK has higher volatility (13.52%) compared to BSTZ (11.24%). In terms of maximum drawdown, STK dropped -41.74% vs BSTZ's -60.51%.

Which has better risk-adjusted returns?

STK currently has the higher Sharpe Ratio (3.64 vs 2.96), 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.