Self managed superannuation trustees have shrugged off the impact of falling interest rates this year and increased their holdings in at-call accounts and term deposits.According to the latest Australian Taxation Office SMSF statistical report, self managed fund holdings in at-call accounts and TDs rose 1.2 per cent from A$155.7 billion in the March quarter to $157.7 per cent in the June quarter.Cash and TDs made up 27 per cent of SMSF assets in the June quarter. The only asset class that makes up a higher proportion of SMSF assets is Australian shares, which are worth $187.1 billion.In the June quarter there were 557,000 SMSFs with total assets of $590 billion.The Reserve Bank has cut the cash rate twice this year - by 25 basis points in February and 25 bps in May.At-call and TD holdings in SMSFs rose by two per cent over the six months to June.