AYMYX — High-Yield Municipal Fund
Data updated: 2026-07-31
AYMYX — High-Yield Municipal Fund data: holdings, portfolio allocation, expenses, performance, cashflows, risk and SEC filings. Long Corporate Bond · $577.04M AUM · 0.37% expense ratio · 3.8% 1-yr return. From SEC regulatory filings.
AYMYX Fund Overview
AYMYX — High-Yield Municipal Fund is a US mutual fund managed by American Century Municipal Trust, categorised as Long Corporate Bond. ABC INVEST provides holdings, performance, costs, cashflows, risk data, prospectus documents and SEC filings, sourced from SEC filings.
- Type: US mutual fund
- Manager: American Century Municipal Trust
- Category: Long Corporate Bond
- Assets under management: $577.04M
- 1-year return: 3.8%
- Ticker: AYMYX
- SEC CIK: 0000746458
- SEC series ID: S000006471
- Share class ID: C000189766
AYMYX Holdings
Top 10 holdings of High-Yield Municipal Fund by percentage of net assets, from the fund's latest SEC N-PORT filing.
| Holding | % of net assets |
|---|---|
| Buckeye Tobacco Settlement Financing Authority | 1.11% |
| Riverspring Hlth Senior | 1.03% |
| Central Plains Energy Project | 0.91% |
| New Jersey Transportation Trust Fund Authority | 0.89% |
| Public Finance Authority | 0.88% |
| Port Newark Container | 0.87% |
| Frndshp Vlg St Louis Oblg | 0.86% |
| Baptist Hosp, Inc. Oblig Gp | 0.75% |
| City of New York NY | 0.71% |
| Uipa Crossroads Public Infrastructure District | 0.68% |
AYMYX Portfolio Allocation
Asset-class allocation of High-Yield Municipal Fund by percentage of net assets, from the latest SEC N-PORT filing.
| Asset class | Allocation |
|---|---|
| Fixed Income | 99.0% |
| Equity | 0.3% |
AYMYX Performance
Total returns for AYMYX (as of 2026-08-01), from SEC filings.
| Period | Total return |
|---|---|
| YTD | 2.4% |
| 1 year | 3.8% |
| 3 years (annualised) | 5.5% |
| 5 years (annualised) | 1.6% |
AYMYX Risk Information
Risk metrics for AYMYX, derived from monthly returns in SEC filings.
- 1-year volatility (annualised): 5.0%
AYMYX Costs and Fees
AYMYX costs about $37 per $10,000 invested per year in fund expenses.
- Net expense ratio: 0.37%
- Gross expense ratio: 0.37%
- Portfolio turnover: 47%
- Brokerage commissions: 0.03 bps of average net assets (SEC N-CEN)
AYMYX Cashflows
Over the 12 months to 2026-02, High-Yield Municipal Fund had net outflows of $19.08M, from monthly SEC N-PORT filings.
| Month | Net flow |
|---|---|
| 2026-02 | $7.35M |
| 2026-01 | $298.78K |
| 2025-12 | −$8.18M |
| 2025-11 | $5.05M |
| 2025-10 | −$8.57M |
| 2025-09 | −$22.25M |
AYMYX Debt Constituents
Largest debt holdings of High-Yield Municipal Fund by percentage of net assets, from the latest SEC N-PORT filing.
| Debt holding | % of net assets |
|---|---|
| Buckeye Tobacco Settlement Financing Authority | 1.11% |
| Riverspring Hlth Senior | 1.03% |
| Central Plains Energy Project | 0.91% |
| New Jersey Transportation Trust Fund Authority | 0.89% |
| Public Finance Authority | 0.88% |
| Port Newark Container | 0.87% |
| Frndshp Vlg St Louis Oblg | 0.86% |
| Baptist Hosp, Inc. Oblig Gp | 0.75% |
| City of New York NY | 0.71% |
| Uipa Crossroads Public Infrastructure District | 0.68% |
AYMYX Prospectus and SEC Filings
Official High-Yield Municipal Fund filings on SEC EDGAR — prospectus, portfolio holdings and annual reports.
Related Funds
Other Long Corporate Bond funds tracked on ABC INVEST:
Data Sources
ABC INVEST compiles this page from public filings made to the U.S. Securities and Exchange Commission (SEC) through EDGAR: portfolio holdings and monthly cashflows from Form N-PORT, expenses and returns from fund prospectuses (Form 485BPOS) and the SEC DERA Risk/Return Summary data sets, annual data from Form N-CEN, and shareholder reports from Form N-CSR.